National Library of Energy BETA

Sample records for laser-driven electron source

  1. The investigation of high intensity laser driven micro neutron sources

    E-Print Network [OSTI]

    Ghoniem, Nasr M.

    , access to high temperature states of mat- ter capable of thermonuclear fusion and/or the effi- cientThe investigation of high intensity laser driven micro neutron sources for fusion materials. The application of fast pulse, high intensity lasers to drive low cost DT point neutron sources for fusion

  2. A Hybrid Laser-driven E-beam Injector Using Photo-cathode Electron Gun and superconducting Cavity*

    E-Print Network [OSTI]

    Geng, Rong-Li

    A Hybrid Laser-driven E-beam Injector Using Photo-cathode Electron Gun and superconducting Cavity, Beijing 100871, China * Work supported by NNSF of China Abstract A laser-driven photo-cathode electron gun constructed and tested. As the next step, a hybrid photo-injector, using a DC laser-driven electron gun

  3. GeV ELECTRON BEAMS FROM A CENTIMETER-SCALE LASER-DRIVEN PLASMA ACCELERATOR

    E-Print Network [OSTI]

    Geddes, Cameron Guy Robinson

    GeV ELECTRON BEAMS FROM A CENTIMETER-SCALE LASER-DRIVEN PLASMA ACCELERATOR A. J. Gonsalves, K discharge waveguide [1, 2]. Electron beams were not observed without a plasma channel, indicating that self of the electron beam spectra, and the dependence of the reliability of pro- ducing electron beams as a function

  4. Laser-driven electron acceleration in infinite vacuum

    E-Print Network [OSTI]

    Wong, Liang Jie

    2011-01-01

    I first review basic models for laser-plasma interaction that explain electron acceleration and beam confinement in plasma. Next, I discuss ponderomotive electron acceleration in infinite vacuum, showing that the transverse ...

  5. Microstructure-based laser-driven free-electron laser T. Plettner , R.L. Byer

    E-Print Network [OSTI]

    Byer, Robert L.

    Keywords: Dielectric-structure undulator Laser-driven particle acceleration Phase-synchronous deflection with future structure-loaded laser-driven particle accelerators. These accelerators are expected to operate-tabletop system that is based on this accelerator, a matching compact undulator is highly desirable. To this end

  6. All-laser-driven, MeV-energy X-ray source for detection of SNM Sudeep Banerjee, Nathan Powers, Vidya Ramanathan, Nathaniel Cunningham, Nate Chandler-Smith, Shouyuan

    E-Print Network [OSTI]

    Umstadter, Donald

    All-laser-driven, MeV-energy X-ray source for detection of SNM Sudeep Banerjee, Nathan Powers-power on a supersonic helium nozzle to drive a relativistic plasma wave (laser wakefield). Electron beams with energies-monoenergetic x-rays offer significant advantages for the detection of sensitive nuclear materials using

  7. Photonic-based laser driven electron beam deflection and focusing structures T. Plettner,* R. L. Byer, and C. McGuinness

    E-Print Network [OSTI]

    Byer, Robert L.

    Photonic-based laser driven electron beam deflection and focusing structures T. Plettner,* R. L, and for beam switching. Generation of beams consisting of electron pulses with sub-fsec duration from laser of other devices that manipulate sub-fsec electron beams. The compactness of the proposed deflection device

  8. Compact laser-driven electron acceleration, bunch compression and coherent nonlinear Thomson scattering

    E-Print Network [OSTI]

    Wong, Liang Jie

    2013-01-01

    Coherent hard x-rays have many medical, commercial and academic research applications. To facilitate the design of a table-top coherent hard x-ray source, this thesis studies the linear acceleration of electrons by optical ...

  9. Effects of initially energetic electrons on relativistic laser-driven electron plasma waves

    SciTech Connect (OSTI)

    Yazdanpanah, J., E-mail: jamal.yazdan@gmail.com; Anvari, A. [Department of Physics, Sharif University of Technology, P.O. Box 1155-4161, Tehran (Iran, Islamic Republic of)] [Department of Physics, Sharif University of Technology, P.O. Box 1155-4161, Tehran (Iran, Islamic Republic of)

    2014-02-15

    In this paper, using kinetic calculations and accurate 1D2V particle-in-cell simulations, we point out the important role of initially energetic electrons of the distribution tail in the behavior of high amplitude electron plasma waves (EPWs). In the presence of these electrons, the conventional warm fluid theory (WFT) breaks at very high wave amplitudes that are still noticeably lower than the wave breaking amplitude (WBA). The fluid breakdown results in electron super-heating with respect to the adiabatic laws. Indeed, a new kinetic regime of the relativistic EPWs appears below the WBA. It is argued that the mentioned super-heating results in WBA values lower than the corresponding WFT prediction.

  10. Laser driven compact ion accelerator

    DOE Patents [OSTI]

    Tajima, Toshiki

    2005-03-15

    A laser driven compact ion source including a light source that produces an energy pulse, a light source guide that guides the energy pulse to a target and produces an ion beam. The ion beam is transported to a desired destination.

  11. 1 GeV Electron Beams from a Laser-Driven Channel-Guided Accelerator

    E-Print Network [OSTI]

    Geddes, Cameron Guy Robinson

    energy lasers. The radiation pressure of an intense laser pulse drives a space charge wave in a plasma [1 particle accelerators for radiation sources, high-energy physics, and other applications are typically machines. A different technology for generating intense energetic electron beams and synchronized

  12. Bright X-ray source from a laser-driven micro-plasma-waveguide

    E-Print Network [OSTI]

    Yi, Longqing; Thanh, Phuc Luu; Shen, Baifei

    2015-01-01

    Bright tunable x-ray sources have a number of applications in basic science, medicine and industry. The most powerful sources are synchrotrons, where relativistic electrons are circling in giant storage rings. In parallel, compact laser-plasma x-ray sources are being developed. Owing to the rapid progress in laser technology, very high-contrast femtosecond laser pulses of relativistic intensities become available. These pulses allow for interaction with micro-structured solid-density plasma without destroying the structure by parasitic pre-pulses. The high-contrast laser pulses as well as the manufacturing of materials at micro- and nano-scales open a new realm of possibilities for laser interaction with photonic materials at the relativistic intensities. Here we demonstrate, via numerical simulations, that when coupling with a readily available 1.8 Joule laser, a micro-plasma-waveguide (MPW) may serve as a novel compact x-ray source. Electrons are extracted from the walls by the laser field and form a dense ...

  13. Free Electron Lasers Seeded by ir Laser Driven High-order Harmonic Generation

    SciTech Connect (OSTI)

    Wu, Juhao; Bolton, Paul R.; /SLAC; Murphy, James B.; /BNL, NSLS; Zhong, Xinming; /Beijing Normal U.

    2007-03-12

    Coherent x-ray production by a seeded free electron laser (FEL) is important for next generation synchrotron light sources. We examine the feasibility and features of FEL emission seeded by a high-order harmonic of an infrared laser (HHG). In addition to the intrinsic FEL chirp, the longitudinal profile and spectral bandwidth of the HHG seed are modified significantly by the FEL interaction well before saturation. This smears out the original attosecond pulselet structure. We introduce criteria for this smearing effect on the pulselet and the stretching effect on the entire pulse. We discuss the noise issue in such a seeded FEL.

  14. GeV electron beams from a centimeter-scale laser-driven plasma accelerator

    E-Print Network [OSTI]

    2008-01-01

    GeV electron beams from cm-scale channel guided laser wake?the generation of GeV-class electron beams using an intenseranges and high-quality electron beams with energy up to 1

  15. Two-color-laser-driven direct electron acceleration in infinite vacuum

    E-Print Network [OSTI]

    Wong, Liang Jie

    We propose a direct electron acceleration scheme that uses a two-color pulsed radially polarized laser beam. The two-color scheme achieves electron acceleration exceeding 90% of the theoretical energy gain limit, over twice ...

  16. Electronic excitation as a mode of heat dissipation in laser-driven cluster plasmas

    SciTech Connect (OSTI)

    Rajeev, R.; Rishad, K. P. M.; Madhu Trivikram, T.; Krishnamurthy, M.

    2013-12-15

    Electrons streaming out of laser plasma are known for non-local heat transport and energy deposition by the ionization wave. At 100 eV electron temperature, since the electronic excitation cross section is comparable to that of ionization for Ar and CO{sub 2}, a non-local excitation wave akin to the ionization wave is envisaged where energy deposition in excitations forms a excited cluster sheath beyond the laser focus. Here, we show that nano-cluster systems have the right parameters to form such an exciton sheath and experimentally demonstrate this via charge transfer reactions.

  17. Compact disposal of high-energy electron beams using passive or laser-driven plasma decelerating stage

    SciTech Connect (OSTI)

    Bonatto, A.; Schroeder, C.B.; Vay, J.-L.; Geddes, C.R.; Benedetti, C.; Esarey and, E.; Leemans, W.P.

    2014-07-13

    A plasma decelerating stage is investigated as a compact alternative for the disposal of high-energy beams (beam dumps). This could benefit the design of laser-driven plasma accelerator (LPA) applications that require transportability and or high-repetition-rate operation regimes. Passive and laser-driven (active) plasma-based beam dumps are studied analytically and with particle-in-cell (PIC) simulations in a 1D geometry. Analytical estimates for the beam energy loss are compared to and extended by the PIC simulations, showing that with the proposed schemes a beam can be efficiently decelerated in a centimeter-scale distance.

  18. Calibration of Time Of Flight Detectors Using Laser-driven Neutron Source

    E-Print Network [OSTI]

    S. R. Mirfayzi; S. Kar; H. Ahmed; A. G. Krygier; A. Green; A. Alejo; R. Clarke; R. R. Freeman; J. Fuchs; D. Jung; A. Kleinschmidt; J. T. Morrison; Z. Najmudin; H. Nakamura; P. Norreys; M. Oliver; M. Roth; L. Vassura; M. Zepf; M. Borghesi

    2015-06-15

    Calibration of three scintillators (EJ232Q, BC422Q and EJ410) in a time-of-flight (TOF) arrangement using a laser drive-neutron source is presented. The three plastic scintillator detectors were calibrated with gamma insensitive bubble detector spectrometers, which were absolutely calibrated over a wide range of neutron energies ranging from sub MeV to 20 MeV. A typical set of data obtained simultaneously by the detectors are shown, measuring the neutron spectrum emitted from a petawatt laser irradiated thin foil.

  19. The slingshot effect: A possible new laser-driven high energy acceleration mechanism for electrons

    SciTech Connect (OSTI)

    Fiore, Gaetano; Fedele, Renato; Angelis, Umberto de

    2014-11-15

    We show that under appropriate conditions the impact of a very short and intense laser pulse onto a plasma causes the expulsion of surface electrons with high energy in the direction opposite to the one of the propagations of the pulse. This is due to the combined effects of the ponderomotive force and the huge longitudinal field arising from charge separation (“slingshot effect”). The effect should also be present with other states of matter, provided the pulse is sufficiently intense to locally cause complete ionization. An experimental test seems to be feasible and, if confirmed, would provide a new extraction and acceleration mechanism for electrons, alternative to traditional radio-frequency-based or laser-wake-field ones.

  20. The slingshot effect: a possible new laser-driven high energy acceleration mechanism for electrons

    E-Print Network [OSTI]

    Gaetano Fiore; Renato Fedele; Umberto de Angelis

    2014-11-14

    We show that under appropriate conditions the impact of a very short and intense laser pulse onto a plasma causes the expulsion of surface electrons with high energy in the direction opposite to the one of propagation of the pulse. This is due to the combined effects of the ponderomotive force and the huge longitudinal field arising from charge separation ("slingshot effect"). The effect should also be present with other states of matter, provided the pulse is sufficiently intense to locally cause complete ionization. An experimental test seems to be feasible and, if confirmed, would provide a new extraction and acceleration mechanism for electrons, alternative to traditional radio-frequency-based or Laser-Wake-Field ones.

  1. Direct observation of ultrafast surface transport of laser-driven fast electrons in a solid target

    SciTech Connect (OSTI)

    Singh, Prashant Kumar; Chatterjee, Gourab; Adak, Amitava; Ahmed, Saima; Lad, Amit D.; Ravindra Kumar, G.; Cui, Y. Q.; Wang, W. M.; Sheng, Z. M.; Key Laboratory for Laser Plasmas , Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240

    2013-11-15

    We demonstrate rapid spread of surface ionization on a glass target excited by an intense, ultrashort laser pulse at an intensity of 3 × 10{sup 17} W cm{sup ?2}. Time- and space-resolved reflectivity of the target surface indicates that the initial plasma region created by the pump pulse expands at c/7. The measured quasi-static megagauss magnetic field is found to expand in a manner very similar to that of surface ionization. Two-dimensional particle-in-cell simulations reproduce measurements of surface ionization and magnetic fields. Both the experiment and simulation convincingly demonstrate the role of self-induced electric and magnetic fields in confining fast electrons along the target-vacuum interface.

  2. PUBLISHED ONLINE: 27 SEPTEMBER 2009 | DOI: 10.1038/NPHYS1404 Laser-driven soft-X-ray undulator source

    E-Print Network [OSTI]

    sources of X-ray radiation. They constitute invaluable tools for a broad range of research1 ; however, their dependence on large- scale radiofrequency electron accelerators means that only a few of these sources exist-laboratory scale. Here, we demonstrate the generation of soft-X-ray undulator radiation with laser

  3. CONCEPTUAL DESIGN OF A BRIGHT ELECTRON INJECTOR BASED ON A LASER-DRIVEN PHOTOCATHODE RF ELECTRON GUN

    E-Print Network [OSTI]

    Chattopadhyay, S.

    2010-01-01

    Photocathode RF Electron Gun S. Chattopadhyay, Y.J. Chen, D.PHOTOCATHODE RF ELECTRON GUN' S. Chnttopndhyny. Y.J. Chen (Photocathode RF Electron Gun S. Chattopadhyay, Y.I. Chen, D.

  4. Proposed dielectric-based microstructure laser-driven undulator T. Plettner and R. L. Byer

    E-Print Network [OSTI]

    Byer, Robert L.

    sources that feed into permanent-magnet undulators. The distinguish- ing feature of the undulator proposed a proposed all-dielectric laser-driven undulator for the generation of coherent short wavelengths and explore-electron radiation concepts for ultrashort coherent wavelength generation are being investigated. For example, active

  5. Characterisation of deuterium spectra from laser driven multi-species sources by employing differentially filtered image plate detectors in Thomson spectrometers

    SciTech Connect (OSTI)

    Alejo, A.; Kar, S. Ahmed, H.; Doria, D.; Green, A.; Jung, D.; Lewis, C. L. S.; Nersisyan, G.; Krygier, A. G.; Freeman, R. R.; Clarke, R.; Green, J. S.; Notley, M.; Fernandez, J.; Fuchs, J.; Kleinschmidt, A.; Roth, M.; Morrison, J. T.; Najmudin, Z.; Nakamura, H.; and others

    2014-09-15

    A novel method for characterising the full spectrum of deuteron ions emitted by laser driven multi-species ion sources is discussed. The procedure is based on using differential filtering over the detector of a Thompson parabola ion spectrometer, which enables discrimination of deuterium ions from heavier ion species with the same charge-to-mass ratio (such as C{sup 6+}, O{sup 8+}, etc.). Commonly used Fuji Image plates were used as detectors in the spectrometer, whose absolute response to deuterium ions over a wide range of energies was calibrated by using slotted CR-39 nuclear track detectors. A typical deuterium ion spectrum diagnosed in a recent experimental campaign is presented, which was produced from a thin deuterated plastic foil target irradiated by a high power laser.

  6. Generation of 9 MeV -rays by all-laser-driven Compton scattering with second-harmonic laser light

    E-Print Network [OSTI]

    Umstadter, Donald

    electron beam. Two laser pulses from the same laser system were used: one to accelerate electrons and one, these new ICS sources are driven by laser wakefield acceleration (LWFA) [3,4]. This difference has numerous with each other, by virtue of being driven by the same laser system. Several all-laser- driven approaches

  7. Laser Driven Dynamic Loading of Condensed Matter

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Laser Driven Dynamic Loading of Condensed Matter Laser Driven Dynamic Loading of Condensed Matter Advanced diagnostics of experiments covering many orders of magnitude in strain...

  8. Laser driven ion accelerator

    DOE Patents [OSTI]

    Tajima, Toshiki

    2005-06-14

    A system and method of accelerating ions in an accelerator to optimize the energy produced by a light source. Several parameters may be controlled in constructing a target used in the accelerator system to adjust performance of the accelerator system. These parameters include the material, thickness, geometry and surface of the target.

  9. Laser driven ion accelerator

    DOE Patents [OSTI]

    Tajima, Toshiki

    2006-04-18

    A system and method of accelerating ions in an accelerator to optimize the energy produced by a light source. Several parameters may be controlled in constructing a target used in the accelerator system to adjust performance of the accelerator system. These parameters include the material, thickness, geometry and surface of the target.

  10. 2052 IEEE TRANSACTIONS ON ELECTRON DEVICES, VOL. 35. NO. II, NOVEMBER 1988 Design of the Laser-Driven RF Electron Gun for the

    E-Print Network [OSTI]

    McDonald, Kirk

    -Driven RF Electron Gun for the BNL Accelerator Test Facility KIRK T. McDONALD Abstract-The BNL electron gun due to the effects of space-charge and nonlinear RF fields. The design of the gun was aided diagram of the linac and laser components. Here we report on the design of the electron gun

  11. Krypton Fluoride Laser Driven Inertial Fusion Energy

    E-Print Network [OSTI]

    for Inertial Confinement Fusion Energy Systems San Ramon CA January 29, 2011 presented by John Sethian1 Krypton Fluoride Laser Driven Inertial Fusion Energy Presented to NAS Committee on the Prospects POWER PLANT: Attractive Technology #12;6 Outline S. ObenschainVision of R&D path to Inertial Fusion

  12. Field emission electron source

    DOE Patents [OSTI]

    Zettl, Alexander Karlwalter (Kensington, CA); Cohen, Marvin Lou (Berkeley, CA)

    2000-01-01

    A novel field emitter material, field emission electron source, and commercially feasible fabrication method is described. The inventive field emission electron source produces reliable electron currents of up to 400 mA/cm.sup.2 at 200 volts. The emitter is robust and the current it produces is not sensitive to variability of vacuum or the distance between the emitter tip and the cathode. The novel emitter has a sharp turn-on near 100 volts.

  13. Laser-driven plasma-based accelerators: Wakefield excitation, channel guiding, and laser triggered particle injection*

    E-Print Network [OSTI]

    Wurtele, Jonathan

    Laser-driven plasma-based accelerators: Wakefield excitation, channel guiding, and laser triggered; accepted 18 February 1998 Plasma-based accelerators are discussed in which high-power short pulse lasers are the power source, suitably tailored plasma structures provide guiding of the laser beam and support large

  14. Fiber optic mounted laser driven flyer plates

    SciTech Connect (OSTI)

    Paisley, Dennis L.

    1991-01-01

    A laser driven flyer plate where the flyer plate is deposited directly onto the squared end of an optical fiber. The plasma generated by a laser pulse drives the flyer plate toward a target. In another embodiment, a first metal layer is deposited onto the squared end of an optical fiber, followed by a layer of a dielectric material and a second metal layer. The laser pulse generates a plasma in the first metal layer, but the plasma is kept away from the second metal layer by the dielectric layer until the pressure reaches the point where shearing occurs.

  15. Fiber optic mounted laser driven flyer plates

    SciTech Connect (OSTI)

    Paisley, D.L.

    1990-12-31

    This invention is comprised of a laser driven flyer plate where the flyer plate is deposited directly onto the squared end of an optical fiber. The plasma generated by a laser pulse drives the flyer plate toward a target. In another embodiment, a first metal layer is deposited onto the squared end of an optical fiber, followed by a layer of a dielectric material and a second metal layer. The laser pulse generates a plasma in the first metal layer, but the plasma is kept away from the second metal layer by the dielectric layer until the pressure reaches the point where shearing occurs. 2 figs.

  16. Fiber optic mounted laser driven flyer plates

    SciTech Connect (OSTI)

    Paisley, D.L.

    1991-07-09

    A laser driven flyer plate is described where the flyer plate is deposited directly onto the squared end of an optical fiber. The plasma generated by a laser pulse drives the flyer plate toward a target. In another embodiment, a first metal layer is deposited onto the squared end of an optical fiber, followed by a layer of a dielectric material and a second metal layer. The laser pulse generates a plasma in the first metal layer, but the plasma is kept away from the second metal layer by the dielectric layer until the pressure reaches the point where shearing occurs.

  17. Fiber optic mounted laser driven flyer plates

    SciTech Connect (OSTI)

    Paisley, D.L.

    1990-01-01

    This invention is comprised of a laser driven flyer plate where the flyer plate is deposited directly onto the squared end of an optical fiber. The plasma generated by a laser pulse drives the flyer plate toward a target. In another embodiment, a first metal layer is deposited onto the squared end of an optical fiber, followed by a layer of a dielectric material and a second metal layer. The laser pulse generates a plasma in the first metal layer, but the plasma is kept away from the second metal layer by the dielectric layer until the pressure reaches the point where shearing occurs. 2 figs.

  18. Laser-Driven Mini-Thrusters

    SciTech Connect (OSTI)

    Sterling, Enrique; Lin Jun; Sinko, John; Kodgis, Lisa; Porter, Simon; Pakhomov, Andrew V. [Department of Physics, University of Alabama in Huntsville, Huntsville, AL 35899 (United States); Larson, C. William; Mead, Franklin B. Jr. [Propulsion Directorate, Air Force Research Laboratory, Edwards AFB, CA 93524-7680 (United States)

    2006-05-02

    Laser-driven mini-thrusters were studied using Delrin registered and PVC (Delrin registered is a registered trademark of DuPont) as propellants. TEA CO2 laser ({lambda} = 10.6 {mu}m) was used as a driving laser. Coupling coefficients were deduced from two independent techniques: force-time curves measured with a piezoelectric sensor and ballistic pendulum. Time-resolved ICCD images of the expanding plasma and combustion products were analyzed in order to determine the main process that generates the thrust. The measurements were also performed in a nitrogen atmosphere in order to test the combustion effects on thrust. A pinhole transmission experiment was performed for the study of the cut-off time when the ablation/air breakdown plasma becomes opaque to the incoming laser pulse.

  19. Ultrafast dynamic ellipsometry of laser driven shock waves

    E-Print Network [OSTI]

    Bolme, Cynthia Anne

    2008-01-01

    The experimental measurement technique of ultrafast dynamic ellipsometry (UDE) was developed for measuring material motion and changes in optical properties of samples under laser driven shock loading. Ultrafast dynamic ...

  20. Direct Visualization of Laser-Driven Focusing Shock Waves

    E-Print Network [OSTI]

    Pezeril, Thomas

    Direct real-time visualization and measurement of laser-driven shock generation, propagation, and 2D focusing in a sample are demonstrated. A substantial increase of the pressure at the convergence of the cylindrical ...

  1. Proposed Laser-driven, Dielectric Microstructure Few-cm Long Undulator for Attosecond Coherent X-rays

    SciTech Connect (OSTI)

    Plettner, T; Byer, R.L.; /Stanford U., Ginzton Lab.

    2011-09-16

    This article presents the concept of an all-dielectric laser-driven undulator for the generation of coherent X-rays. The proposed laser-driven undulator is expected to produce internal deflection forces equivalent to a several-Tesla magnetic field acting on a speed-of-light particle. The key idea for this laser-driven undulator is its ability to provide phase synchronicity between the deflection force and the electron beam for a distance that is much greater than the laser wavelength. The potential advantage of this undulator is illustrated with a possible design example that assumes a small laser accelerator which delivers a 2 GeV, 1 pC, 1 kHz electron bunch train to a 10 cm long, 1/2 mm period laser-driven undulator. Such an undulator could produce coherent X-ray pulses with {approx}10{sup 9} photons of 64 keV energy. The numerical modeling for the expected X-ray pulse shape was performed with GENESIS, which predicts X-ray pulse durations in the few-attosecond range. Possible applications for nonlinear electromagnetic effects from these X-ray pulses are briefly discussed.

  2. Sub-100 ps laser-driven dynamic compression of solid deuterium...

    Office of Scientific and Technical Information (OSTI)

    Sub-100 ps laser-driven dynamic compression of solid deuterium with a 40 J laser pulse Citation Details In-Document Search Title: Sub-100 ps laser-driven dynamic compression...

  3. High-power terahertz radiation from relativistic electrons G. L. Carr*, Michael C. Martin, Wayne R. McKinney, K. Jordan,

    E-Print Network [OSTI]

    and, more recently, by table-top laser-driven sources4­6 and by short electron bunches in accelerators the production of high-power broadband THz radiation from sub-picosecond electron bunches in an accelerator with the advent of coherent THz radiation emission from photocarriers in biased semiconductors. Table-top systems

  4. ECR ion source with electron gun

    DOE Patents [OSTI]

    Xie, Z.Q.; Lyneis, C.M.

    1993-10-26

    An Advanced Electron Cyclotron Resonance ion source having an electron gun for introducing electrons into the plasma chamber of the ion source is described. The ion source has a injection enclosure and a plasma chamber tank. The plasma chamber is defined by a plurality of longitudinal magnets. The electron gun injects electrons axially into the plasma chamber such that ionization within the plasma chamber occurs in the presence of the additional electrons produced by the electron gun. The electron gun has a cathode for emitting electrons therefrom which is heated by current supplied from an AC power supply while bias potential is provided by a bias power supply. A concentric inner conductor and outer conductor carry heating current to a carbon chuck and carbon pusher which hold the cathode in place and also heat the cathode. In the Advanced Electron Cyclotron Resonance ion source, the electron gun replaces the conventional first stage used in prior electron cyclotron resonance ion generators. 5 figures.

  5. Surface Functionalization of Silicon Nanoparticles Produced by Laser-Driven Pyrolysis of Silane followed by

    E-Print Network [OSTI]

    Swihart, Mark T.

    Surface Functionalization of Silicon Nanoparticles Produced by Laser-Driven Pyrolysis of Silane. In Final Form: March 15, 2004 CO2 laser induced pyrolysis of silane was used to produce silicon quantities of silicon nanoparticles by laser-driven pyrolysis of silane followed by an HF- HNO3 etching

  6. Transition state theory for laser-driven reactions

    SciTech Connect (OSTI)

    Kawai, Shinnosuke; Bandrauk, Andre D.; Jaffe, Charles; Bartsch, Thomas; Palacian, Jesus; Uzer, T.

    2007-04-28

    Recent developments in transition state theory brought about by dynamical systems theory are extended to time-dependent systems such as laser-driven reactions. Using time-dependent normal form theory, the authors construct a reaction coordinate with regular dynamics inside the transition region. The conservation of the associated action enables one to extract time-dependent invariant manifolds that act as separatrices between reactive and nonreactive trajectories and thus make it possible to predict the ultimate fate of a trajectory. They illustrate the power of our approach on a driven Henon-Heiles system, which serves as a simple example of a reactive system with several open channels. The present generalization of transition state theory to driven systems will allow one to study processes such as the control of chemical reactions through laser pulses.

  7. Hydrodynamic analysis of laser-driven cylindrical implosions

    SciTech Connect (OSTI)

    Ramis, R. [E.T.S.I. Aeronáuticos, Universidad Politécnica de Madrid (Spain)] [E.T.S.I. Aeronáuticos, Universidad Politécnica de Madrid (Spain)

    2013-08-15

    Three-dimensional hydrodynamic simulations are performed to study laser-driven cylindrical implosions in the context of experiments (F. Perez et al., Plasma Phys. Controlled Fusion 51, 124035 (2009)) carried out at the Rutherford Appleton Laboratory in the framework of the HiPER project. The analysis is carried out by using the 3D version of the hydrocode MULTI (R. Ramis et al., Comput. Phys. Commun. 49, 475-505 (1988)). The influence of the main laser parameters on implosion performance and symmetry is consistently studied and compared with the results of 2D analysis. Furthermore, the effects of uncertainties in laser irradiation (pointing, focusing, power balance, and time jitter) on implosion performance (average peak density and temperature) are studied by means of statistical analysis.

  8. ECR ion source with electron gun

    DOE Patents [OSTI]

    Xie, Zu Q. (El Cerrito, CA); Lyneis, Claude M. (Berkeley, CA)

    1993-01-01

    An Advanced Electron Cyclotron Resonance ion source (10) having an electron gun (52) for introducing electrons into the plasma chamber (18) of the ion source (10). The ion source (10) has a injection enclosure (12) and a plasma chamber tank (14). The plasma chamber (18) is defined by a plurality of longitudinal magnets (16). The electron gun (52) injects electrons axially into the plasma chamber (18) such that ionization within the plasma chamber (18) occurs in the presence of the additional electrons produced by the electron gun (52). The electron gun (52) has a cathode (116) for emitting electrons therefrom which is heated by current supplied from an AC power supply (96) while bias potential is provided by a bias power supply (118). A concentric inner conductor (60) and Outer conductor (62) carry heating current to a carbon chuck (104) and carbon pusher (114) Which hold the cathode (116) in place and also heat the cathode (16). In the Advanced Electron Cyclotron Resonance ion source (10), the electron gun (52) replaces the conventional first stage used in prior art electron cyclotron resonance ion generators.

  9. The Electron Beam Ion Source (EBIS)

    ScienceCinema (OSTI)

    Brookhaven Lab

    2010-01-08

    Brookhaven National Lab has successfully developed a new pre-injector system, called the Electron Beam Ion Source, for the Relativistic Heavy Ion Collider (RHIC) and NASA Space Radiation Laboratory science programs. The first of several planned improvemen

  10. Improved operation of the nonambipolar electron source

    SciTech Connect (OSTI)

    Longmier, Ben; Hershkowitz, Noah [University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States)

    2008-09-15

    Significant improvements have been made to the nonambipolar electron source (NES), a radio frequency (rf) plasma-based electron source that does not rely on electron emission at a cathode surface [B. Longmier, S. Baalrud, and N. Hershkowitz, Rev. Sci. Instrum. 77, 113504 (2006)]. A prototype NES has produced 30 A of continuous electron current, using 2 SCCM (SCCM denotes cubic centimeter per minute at STP) Xe, 1300 W rf power at 13.56 MHz, yielding a 180 times gas utilization factor. A helicon mode transition has also been identified during NES operation with an argon propellant, using 15 SCCM Ar, 1000 W rf, and 100 G magnetic field. This NES technology has the ability to replace hollow cathode electron sources and to enable high power electric propulsion missions, eliminating one of the lifetime restrictions that many ion thrusters have previously been faced with.

  11. 43 PARTICLE ACCELERATORS; ELECTRON GUNS; BEAM EMITTANCE; CHARGE

    Office of Scientific and Technical Information (OSTI)

    SPACE 430200* -- Particle Accelerators-- Beam Dynamics, Field Calculations, & Ion Optics The evolution of the electron-beam phase space distribution in laser-driven rf guns is...

  12. Hugoniot and spall data from the laser-driven miniflyer

    SciTech Connect (OSTI)

    Warnes, R.H.; Paisley, D.L.; Tonks, D.L.

    1996-05-01

    The laser-driven miniflyer has been developed as a small-sized complement to the propellant- or gas-driven gun with which to make material property measurements. Flyer velocities typically range from 0.5 to 1.5 km/s, depending on the energy of the launching laser and the flyer dimensions. The 10{endash}50 {mu}m-thick flyers, 1{endash}3 mm in diameter, and comparably small targets require very little material and are easy to recover for post-experiment analysis. To measure and improve the precision of our measurements, we are conducting an extensive series of experiments impacting well-characterized Cu, Al, and Au on several transparent, calibrated, windows (PMMA, LiF, and sapphire). Measurement of the impact and interface velocities with a high-time-resolution velocity interferometer (VISAR) gives us a point on the Hugoniot of the flyer material. These are then compared to published Hugoniot data taken with conventional techniques. In the spall experiments, a flyer strikes a somewhat thicker target of the same material and creates a spall in the target. Measuring the free-surface velocity of the target gives information on the compressive elastic-plastic response of the target to the impact, the tensile spall strength, and the strain rate at which the spall occurred. Volumetric strain rates at spall in these experiments are frequently in the 10{sup 6}{endash}10{sup 8}s{sup {minus}1} range, considerably higher than the 10{sup 3}{endash}10{sup 4}s{sup {minus}1} range obtainable from gas gun experiments. {copyright} {ital 1996 American Institute of Physics.}

  13. Hugoniot and spall data from the laser-driven miniflyer

    SciTech Connect (OSTI)

    Warnes, R.H.; Paisley, D.L.; Tonks, D.L.

    1995-09-01

    The laser-driven miniflyer has been developed as a small-sized complement to the propellant or gas-driven gun with which to make material property measurements. Flyer velocities typically range from 0.5 to 1.5 km/s, depending on the energy of the launching laser and the flyer dimensions. The 10--50 {micro}m-thick flyers, 1--3 mm in diameter, and comparably small targets require very little material and are easy to recover for post-experiment analysis. To measure and improve the precision of the measurements, the authors are conducting an extensive series of experiments impacting well-characterized Cu, Al, and Au on several transparent, calibrated, windows (PMMA, LiF, and sapphire). Measurement of the impact and interface velocities with a high-time-resolution velocity interferometer (VISAR) gives them a point on the Hugoniot of the flyer material. These are then compared to published Hugoniot data taken with conventional techniques. In the spall experiments, a flyer strikes a somewhat thicker target of the same material and creates a spall in the target. Measuring the free-surface velocity of the target gives information on the compressive elastic-plastic response of the target to the impact, the tensile spall strength, and the strain rate at which the spall occurred. Volumetric strain rates at spall in these experiments are frequently in the 10{sup 6}--10{sup 8} s{sup {minus}1} range, considerably higher than the 10{sup 3}--10{sup 4} s{sup {minus}1} range obtainable from gas gun experiments.

  14. Electron beam ion source and electron beam ion trap (invited)

    SciTech Connect (OSTI)

    Becker, Reinard [Scientific Software Service, Kapellenweg 2a, D-63571 Gelnhausen (Germany); Kester, Oliver [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States)

    2010-02-15

    The electron beam ion source (EBIS) and its trap variant [electron beam ion trap (EBIT)] celebrated their 40th and 20th anniversary, respectively, at the EBIS/T Symposium 2007 in Heidelberg. These technologically challenging sources of highly charged ions have seen a broad development in many countries over the last decades. In contrast to most other ion sources the recipe of improvement was not ''sorcery'' but a clear understanding of the physical laws and obeying the technological constraints. This review will report important achievements of the past as well as promising developments in the future.

  15. Laser-driven, magnetized quasi-perpendicular collisionless shocks on the Large Plasma Devicea)

    E-Print Network [OSTI]

    Carter, Troy

    a laser-plasma with a Z-pinch16 or through field-reversed configuration (FRC) plasma guns.17Laser-driven, magnetized quasi-perpendicular collisionless shocks on the Large Plasma Devicea) D. B, preformed magnetized ambient plasma has been studied by utilizing a unique experimental platform

  16. DENSE MATTER IN LASER DRIVEN FUSION ! LABORATORY EXPERIMENTS R.L. Mc Crory and J. Wilson

    E-Print Network [OSTI]

    Boyer, Edmond

    irradiation to heat and compress a target containing thermonuclear fuel to fusion conditions. This is stillDENSE MATTER IN LASER DRIVEN FUSION ! LABORATORY EXPERIMENTS R.L. Mc Crory and J. Wilson Laboratory. The high power lasers in quaestion were constructed with laser fusion studies as the goal, i

  17. Nonlinear saturation of laser driven plasma beat wave by oscillating two-stream instability

    E-Print Network [OSTI]

    Singh, Kunwar Pal

    . K. Sharma Center for Energy Studies, Indian Institute of Technology, New Delhi-110016, India N. K and a low frequency electrostatic mode. The decayed sidebands divert the energy of plasma beat waveNonlinear saturation of laser driven plasma beat wave by oscillating two-stream instability D. N

  18. Laser-driven proton scaling laws and new paths towards energy increase

    E-Print Network [OSTI]

    Loss, Daniel

    -particle radiography8 , or for the production of high-energy-density matter of interest for astrophysics9 ; they couldARTICLES Laser-driven proton scaling laws and new paths towards energy increase J. FUCHS1,2 *, P, 85748 Garching, Germany 8 Laboratoire d'Optique Appliqu´ee ­ENSTA, UMR 7639, CNRS, Ecole Polytechnique

  19. Femtosecond laser-electron x-ray source

    DOE Patents [OSTI]

    Hartemann, Frederic V.; Baldis, Hector A.; Barty, Chris P.; Gibson, David J.; Rupp, Bernhard

    2004-04-20

    A femtosecond laser-electron X-ray source. A high-brightness relativistic electron injector produces an electron beam pulse train. A system accelerates the electron beam pulse train. The femtosecond laser-electron X-ray source includes a high intra-cavity power, mode-locked laser and an x-ray optics system.

  20. An Efficient Microwave Power Source: Free-electron Laser Afterburner

    E-Print Network [OSTI]

    Wang, C.

    2008-01-01

    Proceedings of Intense Microwave Pulses (SPIE, Los Angeles,Physics An Efficient Microwave Power Source: Free-Electron4 UC-414 An Efficient Microwave Power Source: Free-electron

  1. Infrared light sources with semimetal electron injection

    DOE Patents [OSTI]

    Kurtz, Steven R. (Albuquerque, NM); Biefeld, Robert M. (Albuquerque, NM); Allerman, Andrew A. (Albuquerque, NM)

    1999-01-01

    An infrared light source is disclosed that comprises a layered semiconductor active region having a semimetal region and at least one quantum-well layer. The semimetal region, formed at an interface between a GaAsSb or GalnSb layer and an InAsSb layer, provides electrons and holes to the quantum-well layer to generate infrared light at a predetermined wavelength in the range of 2-6 .mu.m. Embodiments of the invention can be formed as electrically-activated light-emitting diodes (LEDs) or lasers, and as optically-pumped lasers. Since the active region is unipolar, multiple active regions can be stacked to form a broadband or multiple-wavelength infrared light source.

  2. Quantum description and properties of electrons emitted from pulsed nanotip electron sources

    E-Print Network [OSTI]

    Pavel Lougovski; Herman Batelaan

    2011-03-31

    We present a quantum calculation of the electron degeneracy for electron sources. We explore quantum interference of electrons in the temporal and spatial domain and demonstrate how it can be utilized to characterize a pulsed electron source. We estimate effects of Coulomb repulsion on two-electron interference and show that currently available nano tip pulsed electron sources operate in the regime where the quantum nature of electrons can be made dominant.

  3. ILC Electron Source Gets Help from JLab | Jefferson Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    electrode The cathode electrode is being put to the test in Jefferson Lab's electron gun test stand. This work is part of a research project on the ILC's electron source, which...

  4. High-intensity laser-driven proton acceleration enhancement from hydrogen containing ultrathin targets

    SciTech Connect (OSTI)

    Dollar, F.; Reed, S. A.; Matsuoka, T.; Bulanov, S. S.; Chvykov, V.; Kalintchenko, G.; McGuffey, C.; Rousseau, P.; Thomas, A. G. R.; Willingale, L.; Yanovsky, V.; Krushelnick, K.; Maksimchuk, A.; Litzenberg, D. W.

    2013-09-30

    Laser driven proton acceleration experiments from micron and submicron thick targets using high intensity (2 × 10{sup 21} W/cm{sup 2}), high contrast (10{sup ?15}) laser pulses show an enhancement of maximum energy when hydrogen containing targets were used instead of non-hydrogen containing. In our experiments, using thin (<1?m) plastic foil targets resulted in maximum proton energies that were consistently 20%–100% higher than when equivalent thickness inorganic targets, including Si{sub 3}N{sub 4} and Al, were used. Proton energies up to 20 MeV were measured with a flux of 10{sup 7} protons/MeV/sr.

  5. Interferometry and high speed photography of laser-driven flyer plates

    SciTech Connect (OSTI)

    Paisley, D.L.; Montoya, N.I.; Stahl, D.B.; Garcia, I.A.

    1989-01-01

    Laser-driven thin (2-10-/mu/ thick) plates of aluminum and copper are accelerated to velocities /ge/5 km/s by a 1.06-/mu/ wavelength Nd:YAG 8-10 ns FWHM laser pulse at power densities 0.7-4.0 GW/cm/sup 2/. Accelerations /ge/10/sup 9/ km/s/sup 2/ have been achieved. The acceleration and velocity of these 0.4-1.0-mm-diameter plates are experimentally recorded by velocity interferometry (VISAR) and the planarity of impact by streak photography. 6 refs., 7 figs.

  6. Terahertz-driven linear electron acceleration

    E-Print Network [OSTI]

    Nanni, Emilio Alessandro; Ravi, Koustuban; Fallahi, Arya; Moriena, Gustavo; Miller, R J Dwayne; Kärtner, Franz X

    2014-01-01

    The cost, size and availability of electron accelerators is dominated by the achievable accelerating gradient. Conventional high-brightness radio-frequency (RF) accelerating structures operate with 30-50 MeV/m gradients. Electron accelerators driven with optical or infrared sources have demonstrated accelerating gradients orders of magnitude above that achievable with conventional RF structures. However, laser-driven electron accelerators require intense sources and suffer from low bunch charge, sub-micron tolerances and sub-femtosecond timing requirements due to the short wavelength of operation. Here, we demonstrate the first linear acceleration of electrons with keV energy gain using optically-generated terahertz (THz) pulses. THz-driven accelerating structures enable high-gradient electron accelerators with simple accelerating structures, high repetition rates and significant charge per bunch. Increasing the operational frequency of accelerators into the THz band allows for greatly increased accelerating ...

  7. Diamondoid Monolayers as Monochromatic Electron Source

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    at the ALS to reveal an intriguing feature: monochromatized electron emission from a self-assembled monolayer of diamondoids. This discovery has immediately attracted the...

  8. Uniform heating of materials into the warm dense matter regime with laser-driven quasi-monoenergetic ion beams

    E-Print Network [OSTI]

    Bang, W; Bradley, P A; Vold, E L; Boettger, J C; Fernández, J C

    2015-01-01

    In a recent experiment on the Trident laser facility, a laser-driven beam of quasi-monoenergetic aluminum ions was used to heat solid gold and diamond foils isochorically to 5.5 eV and 1.7 eV, respectively. Here theoretical calculations are presented that suggest the gold and diamond were heated uniformly by these laser-driven ion beams. According to calculations and SESAME equation-of-state tables, laser-driven aluminum ion beams achievable on Trident, with a finite energy spread of (delta E)/E ~ 20%, are expected to heat the targets more uniformly than a beam of 140 MeV aluminum ions with zero energy spread. The robustness of the expected heating uniformity relative to the changes in the incident ion energy spectra is evaluated, and expected plasma temperatures of various target materials achievable with the current experimental platform are presented.

  9. Electron beam ion sources and traps ,,invited... Reinard Beckera)

    E-Print Network [OSTI]

    Electron beam ion sources and traps ,,invited... Reinard Beckera) Institut fu¨r Angewandte Physik, Johann Wolfgang Goethe-Universita¨t, Frankfurt, Germany Presented on 7 September 1999 The electron beam method of stepwise ionization to highest charge states has found applications in electron beam ion

  10. Abstract--Grazing incidence metal mirrors in laser-driven IFE power plants are subject to a variety of threats that result

    E-Print Network [OSTI]

    Tillack, Mark

    Abstract--Grazing incidence metal mirrors in laser-driven IFE power plants are subject to a variety. The GIMM lowers the effective laser power flux without much loss of reflectivity, thus prolonging [4] at UCSD, and help define design windows for the GIMM in a laser-driven IFE power plant

  11. ILC Polarized Electron Source Design and R&D Program

    SciTech Connect (OSTI)

    Brachmann, A.; Sheppard, J.; Zhou, F.; Poelker, M.; /SLAC

    2012-04-06

    The R and D program for the ILC electron focuses on three areas. These are the source drive laser system, the electron gun and photo cathodes necessary to produce a highly polarized electron beam. Currently, the laser system and photo cathode development take place at SLAC's 'ILC Injector Test facility', which is an integrated lab (laser and gun) that allows the production of the electron beam and is equipped with a set of diagnostics, necessary to characterize the source performance. Development of the ILC electron gun takes place at Jefferson Lab, where advanced concepts and technologies for HV DC electron guns for polarized beams are being developed. The goal is to combine both efforts at one facility to demonstrate an electron beam with ILC specifications, which are electron beam charge and polarization as well as the cathode's lifetime. The source parameters are summarized in Table 1. The current schematic design of the ILC central complex is depicted in Figure 1. The electron and positron sources are located and laid out approximately symmetric on either side of the damping rings.

  12. Demonstartion of density dependence of x-ray flux in a laser-driven hohlraum

    SciTech Connect (OSTI)

    Young, P E; Rosen, M D; Hammer, J H; Hsing, W S; Glendinning, S G; Turner, R E; Kirkwood, R; Schein, J; Sorce, C; Satcher, J; Hamza, A; Reibold, R A; Hibbard, R; Landen, O; Reighard, A; McAlpin, S; Stevenson, M; Thomas, B

    2008-02-11

    Experiments have been conducted using laser-driven cylindrical hohlraums whose walls are machined from Ta{sub 2}O{sub 5} foams of 100 mg/cc and 4 g/cc densities. Measurements of the radiation temperature demonstrate that the lower density walls produce higher radiation temperatures than the high density walls. This is the first experimental demonstration of the prediction that this would occur [M. D. Rosen and J. H. Hammer, Phys. Rev. E 72, 056403 (2005)]. For high density walls, the radiation front propagates subsonically, and part of the absorbed energy is wasted by the flow kinetic energy. For the lower wall density, the front velocity is supersonic and can devote almost all of the absorbed energy to heating the wall.

  13. Flower-like squeezing in the motion of a laser-driven trapped ion

    E-Print Network [OSTI]

    Nguyen Ba An; Truong Minh Duc

    2001-11-28

    We investigate the Nth order amplitude squeezing in the fan-state |\\xi ;2k,f>_F which is a linear superposition of the 2k-quantum nonlinear coherent states. Unlike in usual states where an ellipse is the symbol of squeezing, a 4k-winged flower results in the fan state. We first derive the analytical expression of squeezing for arbitrary k, N, f and then study in detail the case of a laser-driven trapped ion characterized by a specific form of the nonlinear function f. We show that the lowest order in which squeezing may appear and the number of directions along which the amplitude may be squeezed depend only on k whereas the precise directions of squeezing are determined also by the other physical parameters involved. Finally, we present a scheme to produce such fan-states.

  14. Progress on a cryogenically cooled RF gun polarized electron source

    SciTech Connect (OSTI)

    Fliller, R.P., III; Edwards, H.; /Fermilab

    2006-08-01

    RF guns have proven useful in multiple accelerator applications. An RF gun capable of producing polarized electrons is an attractive electron source for the ILC or an electron-ion collider. Producing such a gun has proven elusive. The NEA GaAs photocathode needed for polarized electron production is damaged by the vacuum environment in an RF gun. Electron and ion back bombardment can also damage the cathode. These problems must be mitigated before producing an RF gun polarized electron source. In this paper we report continuing efforts to improve the vacuum environment in a normal conducting RF gun by cooling it with liquid nitrogen after a high temperature vacuum bake out. We also report on a design of a cathode preparation chamber to produce bulk GaAs photocathodes for testing in such a gun. Future directions are also discussed.

  15. Energy sources of field-aligned currents: Auroral electron energization

    E-Print Network [OSTI]

    Wright, Andrew N.

    Energy sources of field-aligned currents: Auroral electron energization Andrew N. Wright of field-aligned currents: Auroral electron energization, J. Geophys. Res., 110, A10S08, doi:10.1029/2004JA means no steady energization can be achieved by such a state [Bryant et al., 1992; Bryant, 1999, 2002

  16. Electron energy recovery system for negative ion sources

    DOE Patents [OSTI]

    Dagenhart, William K. (Oak Ridge, TN); Stirling, William L. (Oak Ridge, TN)

    1982-01-01

    An electron energy recovery system for negative ion sources is provided. The system, employs crossed electric and magnetic fields to separate the electrons from ions as they are extracted from a negative ion source plasma generator and before the ions are accelerated to their full kinetic energy. With the electric and magnetic fields oriented 90.degree. to each other, the electrons are separated from the plasma and remain at approximately the electrical potential of the generator in which they were generated. The electrons migrate from the ion beam path in a precessing motion out of the ion accelerating field region into an electron recovery region provided by a specially designed electron collector electrode. The electron collector electrode is uniformly spaced from a surface of the ion generator which is transverse to the direction of migration of the electrons and the two surfaces are contoured in a matching relationship which departs from a planar configuration to provide an electric field component in the recovery region which is parallel to the magnetic field thereby forcing the electrons to be directed into and collected by the electron collector electrode. The collector electrode is maintained at a potential slightly positive with respect to the ion generator so that the electrons are collected at a small fraction of the full accelerating supply voltage energy.

  17. Picture of the Week: Laser-driven neutron source for research and global

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass mapSpeeding access| DepartmentPeerFederal FleetUp inrd IEEE(Journal13 A9

  18. Multifunctional bulk plasma source based on discharge with electron injection

    SciTech Connect (OSTI)

    Klimov, A. S.; Medovnik, A. V.; Tyunkov, A. V.; Savkin, K. P.; Shandrikov, M. V.; Vizir, A. V.

    2013-01-15

    A bulk plasma source, based on a high-current dc glow discharge with electron injection, is described. Electron injection and some special design features of the plasma arc emitter provide a plasma source with very long periods between maintenance down-times and a long overall lifetime. The source uses a sectioned sputter-electrode array with six individual sputter targets, each of which can be independently biased. This discharge assembly configuration provides multifunctional operation, including plasma generation from different gases (argon, nitrogen, oxygen, acetylene) and deposition of composite metal nitride and oxide coatings.

  19. The Polarized Electron Source for the International Collider (ILC) Project

    SciTech Connect (OSTI)

    Brachmann, A.; Clendenin, J.E.; Garwin, E.L.; Ioakeimidi, K.; Kirby, R.e.; Maruyama, T.; Prescott, C.Y.; Sheppard, J.; Turner, J.; Zhou, F.; /SLAC

    2006-12-01

    ILC project will be the next large high energy physics tool that will use polarized electrons (and positrons). For this machine spin physics will play an important role. The polarized electron source design is based on electron injectors built for the Stanford Linear Collider (polarized) and Tesla Test Facility (un-polarized). The ILC polarized electron source will provide a 5GeV spin polarized electron beam for injection into the ILC damping ring. Although most ILC machine parameters have been achieved by the SLC or TTF source, features of both must be integrated into one design. The bunch train structure presents unique challenges to the source laser drive system. A suitable laser system has not yet been demonstrated and is part of the ongoing R&D program for ILC at SLAC. Furthermore, ILC injector R&D incorporates photocathode development, increasing available polarization, and improving operational properties in gun vacuum systems. Another important area of research and development is advancing the design of DC and RF electron gun technology for polarized sources. This presentation presents the current status of the design and outlines aspects of the relevant R&D program carried out within the ILC community.

  20. A compact, versatile low-energy electron beam ion source

    SciTech Connect (OSTI)

    Zschornack, G., E-mail: g.zschornack@hzdr.de [Department of Physics, Dresden University of Technology, 01062 Dresden, Germany and Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research, 01328 Dresden (Germany); König, J.; Schmidt, M.; Thorn, A. [DREEBIT GmbH, 01109 Dresden (Germany)] [DREEBIT GmbH, 01109 Dresden (Germany)

    2014-02-15

    A new compact Electron Beam Ion Source, the Dresden EBIT-LE, is introduced as an ion source working at low electron beam energies. The EBIT-LE operates at an electron energy ranging from 100 eV to some keV and can easily be modified to an EBIT also working at higher electron beam energies of up to 15 keV. We show that, depending on the electron beam energy, electron beam currents from a few mA in the low-energy regime up to about 40 mA in the high-energy regime are possible. Technical solutions as well as first experimental results of the EBIT-LE are presented. In ion extraction experiments, a stable production of low and intermediate charged ions at electron beam energies below 2 keV is demonstrated. Furthermore, X-ray spectroscopy measurements confirm the possibility of using the machine as a source of X-rays from ions excited at low electron energies.

  1. Status of ECR (Electron Cyclotron Resonance) source technology

    SciTech Connect (OSTI)

    Lyneis, C.M.

    1987-03-01

    ECR (Electron Cyclotron Resonance) ion sources are now in widespread use for the production of high quality multiply charged ion beams for accelerators and atomic physics experiments, and industrial applications are being explored. Several general characteristics of ECR sources explain their widespread acceptance. For use with cyclotrons which require CW multiply charged ion beams, the ECR source has many advantages over heavy-ion PIG sources. Most important is the ability to produce higher charge states at useful intensities for nuclear physics experiments. Since the maximum energy set by the bending limit of a cyclotron scales with the square of the charge state, the installation of ECR sources on cyclotrons has provided an economical path to raise the energy. Another characteristic of ECR sources is that the discharge is produced without cathodes, so that only the source material injected into an ECR source is consumed. As a result, ECR sources can be operated continuously for periods of weeks without interruption. Techniques have been developed in the last few years, which allow these sources to produce beams from solid materials. The beam emittance from ECR sources is in the range of 50 to 200 ..pi.. mm-mrad at 10 kV. The principles of ECR ion sources are discussed, and present and future ECR sources are reviewed.

  2. Electron Beam Collimation for the Next Generation Light Source

    SciTech Connect (OSTI)

    Steier, C.; Emma, P.; Nishimura, H.; Papadopoulos, C.; Sannibale, F.

    2013-05-20

    The Next Generation Light Source will deliver high (MHz) repetition rate electron beams to an array of free electron lasers. Because of the significant average current in such a facility, effective beam collimation is extremely important to minimize radiation damage to undulators, prevent quenches of superconducting cavities, limit dose rates outside of the accelerator tunnel and prevent equipment damage. This paper describes the early conceptual design of a collimation system, as well as initial results of simulations to test its effectiveness.

  3. Novel free-form hohlraum shape design and optimization for laser-driven inertial confinement fusion

    SciTech Connect (OSTI)

    Jiang, Shaoen; Jing, Longfei Ding, Yongkun; Huang, Yunbao

    2014-10-15

    The hohlraum shape attracts considerable attention because there is no successful ignition method for laser-driven inertial confinement fusion at the National Ignition Facility. The available hohlraums are typically designed with simple conic curves, including ellipses, parabolas, arcs, or Lame curves, which allow only a few design parameters for the shape optimization, making it difficult to improve the performance, e.g., the energy coupling efficiency or radiation drive symmetry. A novel free-form hohlraum design and optimization approach based on the non-uniform rational basis spline (NURBS) model is proposed. In the present study, (1) all kinds of hohlraum shapes can be uniformly represented using NURBS, which is greatly beneficial for obtaining the optimal available hohlraum shapes, and (2) such free-form uniform representation enables us to obtain an optimal shape over a large design domain for the hohlraum with a more uniform radiation and higher drive temperature of the fuel capsule. Finally, a hohlraum is optimized and evaluated with respect to the drive temperature and symmetry at the Shenguang III laser facility in China. The drive temperature and symmetry results indicate that such a free-form representation is advantageous over available hohlraum shapes because it can substantially expand the shape design domain so as to obtain an optimal hohlraum with high performance.

  4. Numerical model of Electron Cyclotron Resonance Ion Source

    E-Print Network [OSTI]

    Mironov, V; Bondarchenko, A; Efremov, A; Loginov, V

    2015-01-01

    Important features of Electron Cyclotron Resonance Ion Source (ECRIS) operation are accurately reproduced with a numerical code. The code uses the particle-in-cell technique to model a dynamics of ions in ECRIS plasma. It is shown that gas dynamical ion confinement mechanism is sufficient to provide the ion production rates in ECRIS close to the experimentally observed values. Extracted ion currents are calculated and compared to the experiment for few sources. Changes in the extracted ion currents are obtained with varying the gas flow into the source chamber and the microwave power. Empirical scaling laws for ECRIS design are studied and the underlying physical effects are discussed.

  5. Risk Management Plan Electron Beam Ion Source Project

    E-Print Network [OSTI]

    Risk Management Plan for the Electron Beam Ion Source Project (EBIS) Project # 06-SC-002. There are three specific areas of risk that can be controlled and managed by the EBIS Project team and these are and operations. The BNL ISM clearly indicates that risk management is everybody's business and will be factored

  6. Separation of beam and electrons in the spallation neutron source H{sup -} ion source

    SciTech Connect (OSTI)

    Whealton, J.H.; Raridon, R.J.; Leung, K.N.

    1997-12-01

    The Spallation Neutron Source (SNS) requires an ion source producing an H{sup {minus}} beam with a peak current of 35mA at a 6.2 percent duty factor. For the design of this ion source, extracted electrons must be transported and dumped without adversely affecting the H{sup {minus}} beam optics. Two issues are considered: (1) electron containment transport and controlled removal; and (2) first-order H{sup {minus}} beam steering. For electron containment, various magnetic, geometric and electrode biasing configurations are analyzed. A kinetic description for the negative ions and electrons is employed with self-consistent fields obtained from a steady-state solution to Poisson`s equation. Guiding center electron trajectories are used when the gyroradius is sufficiently small. The magnetic fields used to control the transport of the electrons and the asymmetric sheath produced by the gyrating electrons steer the ion beam. Scenarios for correcting this steering by split acceleration and focusing electrodes will be considered in some detail.

  7. A compact x-ray free electron laser

    SciTech Connect (OSTI)

    Barletta, W.A. . Center for Advanced Accelerators Physics Lawrence Livermore National Lab., CA ); Atac, M.; Cline, D.B.; Kolonko, J. . Center for Advanced Accelerators Physics); Bhowmik, A.; Bobbs, B.; Cover, R.A.; Dixon, F.P.; Rakowsky, G. . Rocketdyne Div.); Gallardo

    1988-01-01

    We present a design concept and simulation of the performance of a compact x-ray, free electron laser driven by ultra-high gradient rf-linacs. The accelerator design is based on recent advances in high gradient technology by a LLNL/SLAC/LBL collaboration and on the development of bright, high current electron sources by BNL and LANL. The GeV electron beams generated with such accelerators can be converted to soft x-rays in the range from 2--10 nm by passage through short period, high field strength wigglers as are being designed at Rocketdyne Linear light sources of this type can produce trains of picosecond (or shorter) pulses of extremely high spectral brilliance suitablee for flash holography of biological specimens in vivo and for studies of fast chemical reactions. 12 refs., 8 figs., 4 tabs.

  8. Electron string ion sources for carbon ion cancer therapy accelerators

    E-Print Network [OSTI]

    Boytsov, A Yu; Donets, E D; Donets, E E; Katagiri, K; Noda, K; Ponkin, D O; Ramzdorf, A Yu; Salnikov, V V; Shutov, V B

    2015-01-01

    The Electron String type of Ion Sources (ESIS) was developed, constructed and tested first in the Joint Institute for Nuclear Research. These ion sources can be the appropriate sources for production of pulsed C4+ and C6+ ion beams which can be used for cancer therapy accelerators. In fact the test ESIS Krion-6T already now at the solenoid magnetic field only 4.6 T provides more than 10^10 C4+ ions per pulse and about 5*10^9 C6+ ions per pulse. Such ion sources could be suitable for application at synchrotrons. It was also found, that Krion-6T can provide more than 10^11 C6+ ions per second at 100 Hz repetition rate, and the repetition rate can be increased at the same or larger ion output per second. This makes ESIS applicable at cyclotrons as well. As for production of 11C radioactive ion beams ESIS can be the most economic kind of ion source. To proof that the special cryogenic cell for pulse injection of gaseous species into electron string was successfully tested using the ESIS Krion-2M.

  9. Crystallographic data processing for free-electron laser sources

    SciTech Connect (OSTI)

    White, Thomas A. Barty, Anton; Stellato, Francesco; Holton, James M.; Kirian, Richard A.; Zatsepin, Nadia A.; Chapman, Henry N.

    2013-07-01

    A processing pipeline for diffraction data acquired using the ‘serial crystallography’ methodology with a free-electron laser source is described with reference to the crystallographic analysis suite CrystFEL and the pre-processing program Cheetah. A processing pipeline for diffraction data acquired using the ‘serial crystallography’ methodology with a free-electron laser source is described with reference to the crystallographic analysis suite CrystFEL and the pre-processing program Cheetah. A detailed analysis of the nature and impact of indexing ambiguities is presented. Simulations of the Monte Carlo integration scheme, which accounts for the partially recorded nature of the diffraction intensities, are presented and show that the integration of partial reflections could be made to converge more quickly if the bandwidth of the X-rays were to be increased by a small amount or if a slight convergence angle were introduced into the incident beam.

  10. SU-D-BRE-05: Feasibility and Limitations of Laser-Driven Proton Therapy: A Treatment Planning Study

    SciTech Connect (OSTI)

    Hofmann, K; Wilkens, J [Department of Radiation Oncology, Technische Universitaet Muenchen, Klinikum rechts der Isar (Germany); Masood, U [OncoRay, National Center for Radiation Research in Oncology, Dresden (Germany); Pawelke, J [OncoRay, National Center for Radiation Research in Oncology, Dresden (Germany); Helmholtz-Zentrum Dresden-Rossendorf e.V. (Germany)

    2014-06-01

    Purpose: Laser-acceleration of particles may offer a cost- and spaceefficient alternative for future radiation therapy with particles. Laser-driven particle beams are pulsed with very short bunch times, and a high number of particles is delivered within one laser shot which cannot be portioned or modulated during irradiation. The goal of this study was to examine whether good treatment plans can be produced for laser-driven proton beams and to investigate the feasibility of a laser-driven treatment unit. Methods: An exponentially decaying proton spectrum was tracked through a gantry and energy selection beam line design to produce multiple proton spectra with different energy widths centered on various nominal energies. These spectra were fed into a treatment planning system to calculate spot scanning proton plans using different lateral widths of the beam and different numbers of protons contained in the initial spectrum. The clinical feasibility of the resulting plans was analyzed in terms of dosimetric quality and the required number of laser shots as an estimation of the overall treatment time. Results: We were able to produce treatment plans with plan qualities of clinical relevance for a maximum initial proton number per laser shot of 6*10{sup 8}. However, the associated minimum number of laser shots was in the order of 10{sup 4}, indicating a long delivery time in the order of at least 15 minutes, when assuming an optimistic repetition rate of the laser system of 10 Hz. Conclusion: With the simulated beam line and the assumed shape of the proton spectrum it was impossible to produce clinically acceptable treatment plans that can be delivered in a reasonable time. The situation can be improved by a method or a device in the beam line which can modulate the number of protons from shot to shot. Supported by DFG Cluster of Excellence: Munich-Centre for Advanced Photonics.

  11. Note: Simulation and test of a strip source electron gun

    SciTech Connect (OSTI)

    Iqbal, Munawar; Islam, G. U.; Misbah, I.; Iqbal, O.; Zhou, Z.

    2014-06-15

    We present simulation and test of an indirectly heated strip source electron beam gun assembly using Stanford Linear Accelerator Center (SLAC) electron beam trajectory program. The beam is now sharply focused with 3.04 mm diameter in the post anode region at 15.9 mm. The measured emission current and emission density were 1.12 A and 1.15 A/cm{sup 2}, respectively, that corresponds to power density of 11.5 kW/cm{sup 2}, at 10 kV acceleration potential. The simulated results were compared with then and now experiments and found in agreement. The gun is without any biasing, electrostatic and magnetic fields; hence simple and inexpensive. Moreover, it is now more powerful and is useful for accelerators technology due to high emission and low emittance parameters.

  12. Electron source for a mini ion trap mass spectrometer

    DOE Patents [OSTI]

    Dietrich, Daniel D. (Livermore, CA); Keville, Robert F. (Valley Springs, CA)

    1995-01-01

    An ion trap which operates in the regime between research ion traps which can detect ions with a mass resolution of better than 1:10.sup.9 and commercial mass spectrometers requiring 10.sup.4 ions with resolutions of a few hundred. The power consumption is kept to a minimum by the use of permanent magnets and a novel electron gun design. By Fourier analyzing the ion cyclotron resonance signals induced in the trap electrodes, a complete mass spectra in a single combined structure can be detected. An attribute of the ion trap mass spectrometer is that overall system size is drastically reduced due to combining a unique electron source and mass analyzer/detector in a single device. This enables portable low power mass spectrometers for the detection of environmental pollutants or illicit substances, as well as sensors for on board diagnostics to monitor engine performance or for active feedback in any process involving exhausting waste products.

  13. Electron source for a mini ion trap mass spectrometer

    DOE Patents [OSTI]

    Dietrich, D.D.; Keville, R.F.

    1995-12-19

    An ion trap is described which operates in the regime between research ion traps which can detect ions with a mass resolution of better than 1:10{sup 9} and commercial mass spectrometers requiring 10{sup 4} ions with resolutions of a few hundred. The power consumption is kept to a minimum by the use of permanent magnets and a novel electron gun design. By Fourier analyzing the ion cyclotron resonance signals induced in the trap electrodes, a complete mass spectra in a single combined structure can be detected. An attribute of the ion trap mass spectrometer is that overall system size is drastically reduced due to combining a unique electron source and mass analyzer/detector in a single device. This enables portable low power mass spectrometers for the detection of environmental pollutants or illicit substances, as well as sensors for on board diagnostics to monitor engine performance or for active feedback in any process involving exhausting waste products. 10 figs.

  14. First test of BNL electron beam ion source with high current density electron beam

    SciTech Connect (OSTI)

    Pikin, Alexander Alessi, James G. Beebe, Edward N.; Shornikov, Andrey; Mertzig, Robert; Wenander, Fredrik; Scrivens, Richard

    2015-01-09

    A new electron gun with electrostatic compression has been installed at the Electron Beam Ion Source (EBIS) Test Stand at BNL. This is a collaborative effort by BNL and CERN teams with a common goal to study an EBIS with electron beam current up to 10 A, current density up to 10,000 A/cm{sup 2} and energy more than 50 keV. Intensive and pure beams of heavy highly charged ions with mass-to-charge ratio < 4.5 are requested by many heavy ion research facilities including NASA Space Radiation Laboratory (NSRL) at BNL and HIE-ISOLDE at CERN. With a multiampere electron gun, the EBIS should be capable of delivering highly charged ions for both RHIC facility applications at BNL and for ISOLDE experiments at CERN. Details of the electron gun simulations and design, and the Test EBIS electrostatic and magnetostatic structures with the new electron gun are presented. The experimental results of the electron beam transmission are given.

  15. CONCEPTUAL DESIGN OF A BRIGHT ELECTRON INJECTOR BASED ON A LASER-DRIVEN PHOTOCATHODE RF ELECTRON GUN

    E-Print Network [OSTI]

    Chattopadhyay, S.

    2010-01-01

    on the Relativistic Klystron is presented. The designon the Relativistic Klystron. One of the immediate goals ofas the "relativistic klystron," feeding (2) a high-gradient

  16. Method of electroplating a conversion electron emitting source on implant

    DOE Patents [OSTI]

    Srivastava, Suresh C. (Setauket, NY); Gonzales, Gilbert R. (New York, NY); Adzic, Radoslav (East Setauket, NY); Meinken, George E. (Middle Island, NY)

    2012-02-14

    Methods for preparing an implant coated with a conversion electron emitting source (CEES) are disclosed. The typical method includes cleaning the surface of the implant; placing the implant in an activating solution comprising hydrochloric acid to activate the surface; reducing the surface by H.sub.2 evolution in H.sub.2SO.sub.4 solution; and placing the implant in an electroplating solution that includes ions of the CEES, HCl, H.sub.2SO.sub.4, and resorcinol, gelatin, or a combination thereof. Alternatively, before tin plating, a seed layer is formed on the surface. The electroplated CEES coating can be further protected and stabilized by annealing in a heated oven, by passivation, or by being covered with a protective film. The invention also relates to a holding device for holding an implant, wherein the device selectively prevents electrodeposition on the portions of the implant contacting the device.

  17. Accelerated Electrons as the Source of Auroral Kilometric Radiation R. J. Strangeway

    E-Print Network [OSTI]

    Strangeway, Robert J.

    Accelerated Electrons as the Source of Auroral Kilometric Radiation R. J. Strangeway Institute) have confirmed that Auroral Kilometric Radiation (AKR) is generated by the accelerated electrons in the auroral density cavity. FAST observations of the electron distribution within the AKR source region show

  18. Time-resolved measurements of the hot-electron population in ignition-scale experiments on the National Ignition Facility (invited)

    SciTech Connect (OSTI)

    Hohenberger, M. Stoeckl, C.; Albert, F.; Palmer, N. E.; Döppner, T.; Divol, L.; Dewald, E. L.; Bachmann, B.; MacPhee, A. G.; LaCaille, G.; Bradley, D. K.; Lee, J. J.

    2014-11-15

    In laser-driven inertial confinement fusion, hot electrons can preheat the fuel and prevent fusion-pellet compression to ignition conditions. Measuring the hot-electron population is key to designing an optimized ignition platform. The hot electrons in these high-intensity, laser-driven experiments, created via laser-plasma interactions, can be inferred from the bremsstrahlung generated by hot electrons interacting with the target. At the National Ignition Facility (NIF) [G. H. Miller, E. I. Moses, and C. R. Wuest, Opt. Eng. 43, 2841 (2004)], the filter-fluorescer x-ray (FFLEX) diagnostic–a multichannel, hard x-ray spectrometer operating in the 20–500 keV range–has been upgraded to provide fully time-resolved, absolute measurements of the bremsstrahlung spectrum with ?300 ps resolution. Initial time-resolved data exhibited significant background and low signal-to-noise ratio, leading to a redesign of the FFLEX housing and enhanced shielding around the detector. The FFLEX x-ray sensitivity was characterized with an absolutely calibrated, energy-dispersive high-purity germanium detector using the high-energy x-ray source at NSTec Livermore Operations over a range of K-shell fluorescence energies up to 111 keV (U K{sub ?}). The detectors impulse response function was measured in situ on NIF short-pulse (?90 ps) experiments, and in off-line tests.

  19. RF-driven ion source with a back-streaming electron dump

    DOE Patents [OSTI]

    Kwan, Joe; Ji, Qing

    2014-05-20

    A novel ion source is described having an improved lifetime. The ion source, in one embodiment, is a proton source, including an external RF antenna mounted to an RF window. To prevent backstreaming electrons formed in the beam column from striking the RF window, a back streaming electron dump is provided, which in one embodiment is formed of a cylindrical tube, open at one end to the ion source chamber and capped at its other end by a metal plug. The plug, maintained at the same electrical potential as the source, captures these backstreaming electrons, and thus prevents localized heating of the window, which due to said heating, might otherwise cause window damage.

  20. Laser-driven flat plate impacts to 100 GPA with sub-nanosecond pulse duration and resolution for material property studies

    SciTech Connect (OSTI)

    Paisley, D.L.; Warnes, R.H.; Kopp, R.A.

    1991-01-01

    Miniature laser-driven flat plates (<1-mm diam {times} 0.5--10{mu}m thick, typical) of aluminum, cooper, tungsten, and other materials are accelerated to {le}5 km/s. These miniature plates are used to generate one-dimensional shock waves in solids, liquids, and crystals. Dynamic measurements of spall strength at strain rates {le}10{sup 7} s{sup {minus}1}, elastic-plastic shock wave profiles in 10-{mu}m-thick targets, shocked free-surface acceleration of 10{sup 12} m/s{sup 2}, and laser-driven plate launch accelerations of 10{sup 10} m/s{sup 2} are routinely obtained. The small size of the sample of and projectile mass permits recovery of targets without additional unintended damage or energy deposited into the test specimen. These miniature plates can be launched with conventional 1-J laboratory lasers. 10 refs., 5 figs.

  1. Reply to “Comment on ‘Optically pumped spin-exchange polarized-electron source’ ”

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Pirbhai, M.; Knepper, J.; Litaker, E. T.; Tupa, D.; Gay, T. J.

    2015-05-26

    In the proceeding Comment [1] on our recent report of a Rb spin-exchange polarized-electron source [2], Williams et al. contend: (a) that our source is poorly characterized compared with modern GaAs sources, (b) that we have overstated the difficulties of using GaAs photoemission sources, and (c) that our explanation of various physics issues related to the source's operating principles are not cogent.

  2. Laser-driven shock experiments on precompressed water: Implications for "icy" giant planets

    E-Print Network [OSTI]

    Lee, Kanani K. M.

    believed to contain as much as 50% water by mass and significant amounts of methane and ammonia.1 about the interiors and evolutionary histories of planets.2 Three potential mecha- nisms can generate to the material e.g., ferromagnetism , induction from external sources, or production through electrical cur

  3. Are energetic electrons in the solar wind the source of the outer radiation belt?

    E-Print Network [OSTI]

    Li, Xinlin

    . Mewaldt6 Abstract. Using data from WIND, SAMPEX (Solar, Anomalous, and Magnetospheric Particle Explorer the outer radiation belt electrons. Al- though lower energy electrons in the solar wind could be a seedAre energetic electrons in the solar wind the source of the outer radiation belt? Xinlin Li,1 D. N

  4. Micro-sphere layered targets efficiency in laser driven proton acceleration

    SciTech Connect (OSTI)

    Floquet, V.; Martin, Ph.; Ceccotti, T. [CEA, IRAMIS, SPAM, F-91191 Gif-sur-Yvette (France)] [CEA, IRAMIS, SPAM, F-91191 Gif-sur-Yvette (France); Klimo, O.; Psikal, J.; Limpouch, J.; Proska, J.; Novotny, F.; Stolcova, L. [FNSPE, Czech Technical University in Prague, CR-11519 Prague (Czech Republic)] [FNSPE, Czech Technical University in Prague, CR-11519 Prague (Czech Republic); Velyhan, A. [Institute of Physics v.v.i. ASCR, Na Slovance 1999, Prague (Czech Republic)] [Institute of Physics v.v.i. ASCR, Na Slovance 1999, Prague (Czech Republic); Macchi, A. [Istituto Nazionale di Ottica, Consiglio Nazionale delle Ricerche, research unit “Adriano Gozzini,” Via G. Moruzzi 1, 56124 Pisa (Italy) [Istituto Nazionale di Ottica, Consiglio Nazionale delle Ricerche, research unit “Adriano Gozzini,” Via G. Moruzzi 1, 56124 Pisa (Italy); Dipartimento di Fisica “Enrico Fermi,” Università di Pisa, largo Bruno Pontecorvo 3, 56127 Pisa (Italy); Sgattoni, A. [Dipartimento di Energia, Politecnico di Milano, Milano (Italy) [Dipartimento di Energia, Politecnico di Milano, Milano (Italy); Istituto Nazionale di Ottica, Consiglio Nazionale delle Ricerche, research unit “Adriano Gozzini,” Via G. Moruzzi 1, 56124 Pisa (Italy); Vassura, L. [LULI, UMR7605, CNRS-CEA-Ecole Polytechnique-Paris 6, 91128 Palaiseau (France) [LULI, UMR7605, CNRS-CEA-Ecole Polytechnique-Paris 6, 91128 Palaiseau (France); Dipartimento SBAI, Università di Roma “La Sapienza,” Via A. Scarpa 14, 00161 Roma (Italy); Labate, L.; Baffigi, F.; Gizzi, L. A. [Istituto Nazionale di Ottica, Consiglio Nazionale delle Ricerche, research unit “Adriano Gozzini,” Via G. Moruzzi 1, 56124 Pisa (Italy)] [Istituto Nazionale di Ottica, Consiglio Nazionale delle Ricerche, research unit “Adriano Gozzini,” Via G. Moruzzi 1, 56124 Pisa (Italy)

    2013-08-28

    Proton acceleration from the interaction of high contrast, 25 fs laser pulses at >10{sup 19} W/cm{sup 2} intensity with plastic foils covered with a single layer of regularly packed micro-spheres has been investigated experimentally. The proton cut-off energy has been measured as a function of the micro-sphere size and laser incidence angle for different substrate thickness, and for both P and S polarization. The presence of micro-spheres with a size comparable to the laser wavelength allows to increase the proton cut-off energy for both polarizations at small angles of incidence (10?). For large angles of incidence, however, proton energy enhancement with respect to flat targets is absent. Analysis of electron trajectories in particle-in-cell simulations highlights the role of the surface geometry in the heating of electrons.

  5. ELECTRON-CLOUD MITIGATION IN THE SPALLATION NEUTRON SOURCE RING

    E-Print Network [OSTI]

    Furman, Miguel

    energy at a repeti- tion rate of 60 Hz [1]. At such beam intensity, electron- cloud is expected to be one, and planning of vacuum systems for beam scrubbing upon operation. INTRODUCTION Electron-cloud effects with beam diagnostics. Similar to the Pro- ton Storage Ring at Los Alamos (LANL), where a strong, fast

  6. Apparatus and method for compensating for electron beam emittance in synchronizing light sources

    DOE Patents [OSTI]

    Neil, G.R.

    1996-07-30

    A focused optical beam is used to change the path length of the core electrons in electron light sources thereby boosting their efficiency of conversion of electron beam energy to light. Both coherent light in the free electron laser and incoherent light in the synchrotron is boosted by this technique. By changing the path length of the core electrons by the proper amount, the core electrons are caused to stay in phase with the electrons in the outer distribution of the electron beam. This increases the fraction of the electron beam energy that is converted to light thereby improving the efficiency of conversion of energy to light and therefore boosting the power output of the free electron laser and synchrotron. 4 figs.

  7. Apparatus and method for compensating for electron beam emittance in synchronizing light sources

    DOE Patents [OSTI]

    Neil, George R. (Williamsburg, VA)

    1996-01-01

    A focused optical beam is used to change the path length of the core electrons in electron light sources thereby boosting their efficiency of conversion of electron beam energy to light. Both coherent light in the free electron laser and incoherent light in the synchrotron is boosted by this technique. By changing the path length of the core electrons by the proper amount, the core electrons are caused to stay in phase with the electrons in the outer distribution of the electron beam. This increases the fraction of the electron beam energy that is converted to light thereby improving the efficiency of conversion of energy to light and therefore boosting the power output of the free electron laser and synchrotron.

  8. Laser-driven deflection arrangements and methods involving charged particle beams

    DOE Patents [OSTI]

    Plettner, Tomas (San Ramon, CA); Byer, Robert L. (Stanford, CA)

    2011-08-09

    Systems, methods, devices and apparatus are implemented for producing controllable charged particle beams. In one implementation, an apparatus provides a deflection force to a charged particle beam. A source produces an electromagnetic wave. A structure, that is substantially transparent to the electromagnetic wave, includes a physical structure having a repeating pattern with a period L and a tilted angle .alpha., relative to a direction of travel of the charged particle beam, the pattern affects the force of the electromagnetic wave upon the charged particle beam. A direction device introduces the electromagnetic wave to the structure to provide a phase-synchronous deflection force to the charged particle beam.

  9. Laser-driven miniature flyer plates for shock initiation of secondary explosives

    SciTech Connect (OSTI)

    Paisley, D.L.

    1989-01-01

    Miniature flyer plates (<1-mm diameter X <5-micron thick) of aluminum and other materials are accelerated by a 10-ns pulsed Nd:YAG laser to velocities >5 km/s. Velocity profiles are recorded by velocity interferometry (VISAR) techniques and impact planarity by electronic streak photography. Techniques for improving energy coupling from laser to flyer plate will be discussed. Flyer plate performance parameters will be compared with material properties. The P/sup n/t criteria for shock initiation of explosives will be compared for various flyer materials, pressure, and pulse duration. Performance of secondary explosives (PETN, HNS, HMX, various PBX, others) will be reported. These data will detail the experimental effect of t (in P/sup n/t) approaching values of a few nanoseconds. 9 refs., 5 figs.

  10. Transportation Channel with Uniform Electron Distribution for the Kharkov Neutron Source based on Subcritical Assembly Driven with Linear Accelerator

    E-Print Network [OSTI]

    Zelinsky, A Y

    2008-01-01

    Transportation Channel with Uniform Electron Distribution for the Kharkov Neutron Source based on Subcritical Assembly Driven with Linear Accelerator

  11. Proposed structure for a crossed-laser beam, GeV per meter gradient, vacuum electron linear accelerator

    E-Print Network [OSTI]

    Byer, Robert L.

    Proposed structure for a crossed-laser beam, GeV per meter gradient, vacuum electron linear We propose a dielectric-based, multistaged, laser-driven electron linear accelerator structure operating in a vacuum that is capable of accelerating electrons to 1 TeV in 1 km. Our study shows that a Ge

  12. Production of large resonant plasma volumes in microwave electron cyclotron resonance ion sources

    DOE Patents [OSTI]

    Alton, G.D.

    1998-11-24

    Microwave injection methods are disclosed for enhancing the performance of existing electron cyclotron resonance (ECR) ion sources. The methods are based on the use of high-power diverse frequency microwaves, including variable-frequency, multiple-discrete-frequency, and broadband microwaves. The methods effect large resonant ``volume`` ECR regions in the ion sources. The creation of these large ECR plasma volumes permits coupling of more microwave power into the plasma, resulting in the heating of a much larger electron population to higher energies, the effect of which is to produce higher charge state distributions and much higher intensities within a particular charge state than possible in present ECR ion sources. 5 figs.

  13. Production of large resonant plasma volumes in microwave electron cyclotron resonance ion sources

    DOE Patents [OSTI]

    Alton, Gerald D. (Kingston, TN)

    1998-01-01

    Microwave injection methods for enhancing the performance of existing electron cyclotron resonance (ECR) ion sources. The methods are based on the use of high-power diverse frequency microwaves, including variable-frequency, multiple-discrete-frequency, and broadband microwaves. The methods effect large resonant "volume" ECR regions in the ion sources. The creation of these large ECR plasma volumes permits coupling of more microwave power into the plasma, resulting in the heating of a much larger electron population to higher energies, the effect of which is to produce higher charge state distributions and much higher intensities within a particular charge state than possible in present ECR ion sources.

  14. Development of a high average current polarized electron source with long cathode operational lifetime

    SciTech Connect (OSTI)

    C. K. Sinclair; P. A. Adderley; B. M. Dunham; J. C. Hansknecht; P. Hartmann; M. Poelker; J. S. Price; P. M. Rutt; W. J. Schneider; M. Steigerwald

    2007-02-01

    Substantially more than half of the electromagnetic nuclear physics experiments conducted at the Continuous Electron Beam Accelerator Facility of the Thomas Jefferson National Accelerator Facility (Jefferson Laboratory) require highly polarized electron beams, often at high average current. Spin-polarized electrons are produced by photoemission from various GaAs-based semiconductor photocathodes, using circularly polarized laser light with photon energy slightly larger than the semiconductor band gap. The photocathodes are prepared by activation of the clean semiconductor surface to negative electron affinity using cesium and oxidation. Historically, in many laboratories worldwide, these photocathodes have had short operational lifetimes at high average current, and have often deteriorated fairly quickly in ultrahigh vacuum even without electron beam delivery. At Jefferson Lab, we have developed a polarized electron source in which the photocathodes degrade exceptionally slowly without electron emission, and in which ion back bombardment is the predominant mechanism limiting the operational lifetime of the cathodes during electron emission. We have reproducibly obtained cathode 1/e dark lifetimes over two years, and 1/e charge density and charge lifetimes during electron beam delivery of over 2?105???C/cm2 and 200 C, respectively. This source is able to support uninterrupted high average current polarized beam delivery to three experimental halls simultaneously for many months at a time. Many of the techniques we report here are directly applicable to the development of GaAs photoemission electron guns to deliver high average current, high brightness unpolarized beams.

  15. Note: Design and initial results of a multi-pulsed intense electron beam source

    SciTech Connect (OSTI)

    Xia, L., E-mail: xialiansheng@caep.cn; Zhang, H.; Yang, A.; Shen, Y.; Wang, W.; Wen, L.; Zhang, K.; Shi, J.; Zhang, L.; Deng, J. [Institute of Fluid Physics, CAEP, Mianyang 621900 (China)

    2014-06-15

    A multi-pulsed intense electron beam source is introduced, including the design and the initial experimental results. The source can generate a burst of three pulses of intense electron beams with energy of 2–3 MeV and beam intensities of around 2.5 kA. An inductive adder is chosen to generate the pulsed diode voltages and a dispenser cathode is chosen to emit electron beams. The test results indicate that the design of the source is reliable. The multi-pulsed diode voltage is up to 2.5 MV and the beam intensities are more than 2 kA at the exit of the source with small variation.

  16. Development of a polarized Helium-3 ion source for RHIC using the electron beam ion source

    E-Print Network [OSTI]

    Epstein, Charles Samuel

    2013-01-01

    This thesis presents my work on the design and development of a source of polarized Helium-3 ions for the Relativistic Heavy Ion Collider at Brookhaven National Lab, Upton, NY. The 3He atoms will be polarized using the ...

  17. ELECTRON-CAPTURE SUPERNOVAE AS SOURCES OF {sup 60}Fe

    SciTech Connect (OSTI)

    Wanajo, Shinya [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Janka, Hans-Thomas; Mueller, Bernhard, E-mail: shinya.wanajo@nao.ac.jp [Max-Planck-Institut fuer Astrophysik, Karl-Schwarzschild-Str. 1, D-85748 Garching (Germany)

    2013-09-01

    We investigate the nucleosynthesis of the radionuclide {sup 60}Fe in electron-capture supernovae (ECSNe). The nucleosynthetic results are based on a self-consistent, two-dimensional simulation of an ECSN as well as models in which the densities are systematically increased by some factors (low-entropy models). {sup 60}Fe is found to be appreciably made in neutron-rich ejecta during the nuclear quasi-equilibrium phase with greater amounts being produced in the lower-entropy models. Our results, combining them with the yields of core-collapse supernovae in the literature, suggest that ECSNe account for at least 4%-30% of live {sup 60}Fe in the Milky Way. ECSNe co-produce neutron-rich isotopes, {sup 48}Ca, {sup 50}Ti, {sup 54}Cr, some light trans-iron elements, and possibly weak r-process elements including some radionuclides such as {sup 93}Zr, {sup 99}Tc, and {sup 107}Pd, whose association with {sup 60}Fe might have been imprinted in primitive meteorites or in the deep ocean crust on the Earth.

  18. Simulation and optimization of a 10 A electron gun with electrostatic compression for the electron beam ion source

    SciTech Connect (OSTI)

    Pikin, A.; Beebe, E. N.; Raparia, D.

    2013-03-15

    Increasing the current density of the electron beam in the ion trap of the Electron Beam Ion Source (EBIS) in BNL's Relativistic Heavy Ion Collider facility would confer several essential benefits. They include increasing the ions' charge states, and therefore, the ions' energy out of the Booster for NASA applications, reducing the influx of residual ions in the ion trap, lowering the average power load on the electron collector, and possibly also reducing the emittance of the extracted ion beam. Here, we discuss our findings from a computer simulation of an electron gun with electrostatic compression for electron current up to 10 A that can deliver a high-current-density electron beam for EBIS. The magnetic field in the cathode-anode gap is formed with a magnetic shield surrounding the gun electrodes and the residual magnetic field on the cathode is (5 Division-Sign 6) Gs. It was demonstrated that for optimized gun geometry within the electron beam current range of (0.5 Division-Sign 10) A the amplitude of radial beam oscillations can be maintained close to 4% of the beam radius by adjusting the injection magnetic field generated by a separate magnetic coil. Simulating the performance of the gun by varying geometrical parameters indicated that the original gun model is close to optimum and the requirements to the precision of positioning the gun elements can be easily met with conventional technology.

  19. A low energy ion source for electron capture spectroscopy

    SciTech Connect (OSTI)

    Tusche, C.; Kirschner, J.

    2014-06-15

    We report on the design of an ion source for the production of single and double charged Helium ions with kinetic energies in the range from 300 eV down to 5 eV. The construction is based on a commercial sputter ion gun equipped with a Wien-filter for mass/charge separation. Retardation of the ions from the ionizer potential (2 keV) takes place completely within the lens system of the sputter gun, without modification of original parts. For 15 eV He{sup +} ions, the design allows for beam currents up to 30 nA, limited by the space charge repulsion in the beam. For He{sup 2+} operation, we obtain a beam current of 320?pA at 30 eV, and 46 pA at 5 eV beam energy, respectively. In addition, operating parameters can be optimized for a significant contribution of metastable He*{sup +} (2s) ions.

  20. Tip-based source of femtosecond electron pulses at 30?keV

    SciTech Connect (OSTI)

    Hoffrogge, Johannes; Paul Stein, Jan [Max Planck Institute of Quantum Optics, Hans-Kopfermann-Str. 1, 85748 Garching (Germany); Krüger, Michael; Förster, Michael; Hammer, Jakob; Ehberger, Dominik; Hommelhoff, Peter, E-mail: peter.hommelhoff@fau.de [Max Planck Institute of Quantum Optics, Hans-Kopfermann-Str. 1, 85748 Garching (Germany); Department für Physik, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 1, 91058 Erlangen (Germany); Baum, Peter [Max Planck Institute of Quantum Optics, Hans-Kopfermann-Str. 1, 85748 Garching (Germany); Ludwig-Maximilians-Universität München, Am Coulombwall 1, 85748 Garching (Germany)

    2014-03-07

    We present a nano-scale photoelectron source, optimized for ultrashort pulse durations and well-suited for time-resolved diffraction and advanced laser acceleration experiments. A tungsten tip of several-ten-nanometers diameter mounted in a suppressor-extractor electrode configuration allows the generation of 30?keV electron pulses with an estimated pulse duration of 9?fs (standard deviation; 21?fs full width at half maximum) at the gun exit. We infer the pulse duration from particle tracking simulations, which are in excellent agreement with experimental measurements of the electron-optical properties of the source in the spatial domain. We also demonstrate femtosecond-laser triggered operation of the apparatus. The temporal broadening of the pulse upon propagation to a diffraction sample can be greatly reduced by collimating the beam. Besides the short electron pulse duration, a tip-based source is expected to feature a large transverse coherence and a nanometric emittance.

  1. The TeraFERMI terahertz source at the seeded FERMI free-electron-laser facility

    SciTech Connect (OSTI)

    Perucchi, A. [Sincrotrone Trieste S.C.p.A., Area Science Park, I-34012 Basovizza, Trieste (Italy); INSTM UdR Trieste-ST, Area Science Park, I-34012 Basovizza, Trieste (Italy); Di Mitri, S.; Penco, G.; Allaria, E. [Sincrotrone Trieste S.C.p.A., Area Science Park, I-34012 Basovizza, Trieste (Italy); Lupi, S. [CNR-IOM and Dipartimento di Fisica, Universita di Roma 'La Sapienza', P.le Aldo Moro 2, I-00185 Roma (Italy)

    2013-02-15

    We describe the project for the construction of a terahertz (THz) beamline to be called TeraFERMI at the seeded FERMI free electron laser (FEL) facility in Trieste, Italy. We discuss topics as the underlying scientific case, the choice of the source, the expected performance, and THz beam propagation. Through electron beam dynamics simulations we show that the installation of the THz source in the beam dump section provides a new approach for compressing the electron bunch length without affecting FEL operation. Thanks to this further compression of the FEL electron bunch, the TeraFERMI facility is expected to provide THz pulses with energies up to the mJ range during normal FEL operation.

  2. Electron emission in a source-collector sheath system: A kinetic study

    SciTech Connect (OSTI)

    Rizopoulou, N. Coppins, M.; Bacharis, M.; Robinson, A. P. L.

    2014-10-15

    The classical source-collector sheath system describes a plasma that forms between a Maxwellian source and an absorbing wall. The plasma is assumed to be collisionless and without ionization. Two distinct areas are being formed: the collector sheath, an ion-rich region in contact with the absorbing boundary, and the source sheath, which is an electron-rich area near the Maxwellian source. In this work, we study a modified version of the classical source-collector sheath system, where the wall is no longer absorbing but emits electrons. As a result, we have two different types of collector sheath, one where a potential well is formed and one without a potential well. We examine the effect of electron emission for a range of conditions for the plasma and the emitted electrons. In the first part of this work, we study the problem analytically, and in the second, using our kinetic Vlasov code, Yggdrasil. The simulation results are in very good agreement with the predictions of our theoretical model.

  3. High flux, narrow bandwidth compton light sources via extended laser-electron interactions

    DOE Patents [OSTI]

    Barty, V P

    2015-01-13

    New configurations of lasers and electron beams efficiently and robustly produce high flux beams of bright, tunable, polarized quasi-monoenergetic x-rays and gamma-rays via laser-Compton scattering. Specifically, the use of long-duration, pulsed lasers and closely-spaced, low-charge and low emittance bunches of electron beams increase the spectral flux of the Compton-scattered x-rays and gamma rays, increase efficiency of the laser-electron interaction and significantly reduce the overall complexity of Compton based light sources.

  4. Ultraviolet stimulated electron source for use with low energy plasma instrument calibration

    E-Print Network [OSTI]

    Henderson, Kevin; Funsten, Herb; MacDonald, Elizabeth

    2011-01-01

    We report the development of a versatile, compact, low to medium energy electron source. A collimated, monoenergetic beam of electrons, up to 50 mm in diameter, is produced with energies ranging from 0.03 to 30 keV. A uniform electron beam profile is generated by illuminating a metal cathode plate with a near ultraviolet (UV) light emitting diode (LED). A parallel electric field accelerates the electrons away from the cathode plate towards a grounded grid. The beam intensity can be controlled from 10 - 10^9 electrons cm-2 s-1 and the angular divergence of the beam is less than 1 degree FWHM for energies greater than 1 keV.

  5. Ultraviolet stimulated electron source for use with low energy plasma instrument calibration

    SciTech Connect (OSTI)

    Henderson, Kevin; Harper, Ron; Funsten, Herb; MacDonald, Elizabeth [Space Science and Applications, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2012-07-15

    We have developed and demonstrated a versatile, compact electron source that can produce a mono-energetic electron beam up to 50 mm in diameter from 0.1 to 30 keV with an energy spread of <10 eV. By illuminating a metal cathode plate with a single near ultraviolet light emitting diode, a spatially uniform electron beam with 15% variation over 1 cm{sup 2} can be generated. A uniform electric field in front of the cathode surface accelerates the electrons into a beam with an angular divergence of <1 Degree-Sign at 1 keV. The beam intensity can be controlled from 10 to 10{sup 9} electrons cm{sup -2} s{sup -1}.

  6. A Parametric Study of Electron Extraction from a Low Frequency Inductively Coupled RF-Plasma Source

    E-Print Network [OSTI]

    the arc discharge. Consider instead a non-emitting plasma cathode in which the plasma is produced by rfA Parametric Study of Electron Extraction from a Low Frequency Inductively Coupled RF-Plasma Source and Nathaniel J. Fisch 3 Princeton University Plasma Physics Laboratory, Princeton, NJ 08540, USA Abstract

  7. Multiple species beam production on laser ion source for electron beam ion source in Brookhaven National Laboratory

    SciTech Connect (OSTI)

    Sekine, M., E-mail: sekine.m.ae@m.titech.ac.jp [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, Meguro, Tokyo (Japan); Riken, Wako, Saitama (Japan); Ikeda, S. [Riken, Wako, Saitama (Japan) [Riken, Wako, Saitama (Japan); Department of Energy Science, Tokyo Institute of Technology, Yokohama, Kanagawa (Japan); Hayashizaki, N. [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, Meguro, Tokyo (Japan)] [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, Meguro, Tokyo (Japan); Kanesue, T.; Okamura, M. [Collider-Accelerator Department, Brookhaven National Laboratory, Upton, New York 11973 (United States)] [Collider-Accelerator Department, Brookhaven National Laboratory, Upton, New York 11973 (United States)

    2014-02-15

    Extracted ion beams from the test laser ion source (LIS) were transported through a test beam transport line which is almost identical to the actual primary beam transport in the current electron beam ion source apparatus. The tested species were C, Al, Si, Cr, Fe, Cu, Ag, Ta, and Au. The all measured beam currents fulfilled the requirements. However, in the case of light mass ions, the recorded emittance shapes have larger aberrations and the RMS values are higher than 0.06 ??mm?mrad, which is the design goal. Since we have margin to enhance the beam current, if we then allow some beam losses at the injection point, the number of the single charged ions within the acceptance can be supplied. For heaver ions like Ag, Ta, and Au, the LIS showed very good performance.

  8. Mass spectrometer with electron source for reducing space charge effects in sample beam

    DOE Patents [OSTI]

    Houk, Robert S.; Praphairaksit, Narong

    2003-10-14

    A mass spectrometer includes an ion source which generates a beam including positive ions, a sampling interface which extracts a portion of the beam from the ion source to form a sample beam that travels along a path and has an excess of positive ions over at least part of the path, thereby causing space charge effects to occur in the sample beam due to the excess of positive ions in the sample beam, an electron source which adds electrons to the sample beam to reduce space charge repulsion between the positive ions in the sample beam, thereby reducing the space charge effects in the sample beam and producing a sample beam having reduced space charge effects, and a mass analyzer which analyzes the sample beam having reduced space charge effects.

  9. The laser switched linac and development of a high brilliance electron source

    SciTech Connect (OSTI)

    Melissinos, A.C.; Bamber, C.; Blalock, T.; Fry, A.; Wilson, T.

    1991-09-01

    This task originated in 1987 to explore the possibility of accelerating short bursts of electrons by pulsed power. The principal effort of our group was to demonstrate that electrons can be accelerated by picosecond-long electrical pulses which are compressed in a radial transmission line. This goal has new been achieved and our results are presented in this paper. We have achieved a gradient of 45 MV/m across a 250 {mu}m accelerating gap and have accelerated 10{sup 6} electrons in a 1 ps long pulse. The beam emerges from a 500 {mu}m hole and can be refocused to this transverse dimension. The efficiency of the system, is of order {eta} = 2 {times} 10{sup {minus}6} due to the small number of electrons accelerated. If we identify the gap spacing with one half wavelength of the accelerating r.f.,''our device is equivalent to a 600 GHz structure. The principal limitation in the accelerating gradient comes from the H.V. hold-off properties of the semiconductor disks that are used as photoconductive switches. We believe that with better materials a factor of 10 can be gained in the gradient. Similarly, the electron yield can be increased by at least three orders of magnitude if proper photocathodes are used in place of the metallic surface. The more difficult problem is the engineering of a multicell structure using our present design of the single cell. Our plans for the continuation of this work are given. One of the most promising applications of laser switched acceleration is in the operation of a very low emittance electron source. Thus we have turned our attention to this subject, and in particular to building a high brilliance electron source using a superconducting cavity. Also discussed is the possibility of picosecond x-ray sources.

  10. Electron capture and electron transport by fast ions penetrating solids: An open quantum system approach with sources and sinks

    SciTech Connect (OSTI)

    Seliger, Marek; Reinhold, Carlos O.; Minami, Tatsuya; Schultz, David R.; Pindzola, Michael S.; Yoshida, Shuhei; Burgdoerfer, Joachim; Lamour, Emily; Rozet, Jean-Pierre; Vernhet, Dominique

    2007-03-15

    We present a joint theoretical and experimental study of the time evolution of electronic states of highly charged hydrogenic ions formed by capture during transmission through solids as they undergo multiple collisions and radiative decay. For this transport problem we have developed an inhomogeneous nonunitary Lindblad master equation that allows for a description of open quantum systems with both sinks (electron loss) and source (capture) present. We apply this theoretical framework to study transient coherences created in electron capture by 13.6 MeV/amu Ar{sup 18+} ions transmitted through amorphous carbon foils and decoherence during subsequent interaction with the foil. In the limit of thin targets we can directly probe electron capture cross sections under single collision conditions, while for thicker targets we follow the partially coherent dynamics of the open quantum system in interaction with the solid as a function of interaction time. The calculated results are in close agreement with experimental data obtained at the LISE facility in GANIL. Photon intensities from excited argon ions were determined through high resolution x-ray spectroscopy in which individual fine structure components were resolved. Measurements were performed for a wide range of carbon foil thickness to study the time development of the excited state populations.

  11. Electron Capture and Electron Transport by Fast Ions Penetrating Solids: An open Quantum System Approach with Sources and Sinks

    SciTech Connect (OSTI)

    Seliger, M.

    2007-03-01

    We present a joint theoretical and experimental study of the time evolution of electronic states of highly charged hydrogenic ions formed by capture during transmission through solids as they undergo multiple collisions and radiative decay. For this transport problem we have developed an inhomogeneous nonunitary Lindblad master equation that allows for a description of open quantum systems with both sinks (electron loss) and source (capture) present. We apply this theoretical framework to study transient coherences created in electron capture by 13.6 MeV/amu Ar18+ ions transmitted through amorphous carbon foils and decoherence during subsequent interaction with the foil. In the limit of thin targets we can directly probe electron capture cross sections under single collision conditions, while for thicker targets we follow the partially coherent dynamics of the open quantum system in interaction with the solid as a function of interaction time. The calculated results are in close agreement with experimental data obtained at the LISE facility in GANIL. Photon intensities from excited argon ions were determined through high resolution x-ray spectroscopy in which individual fine structure components were resolved. Measurements were performed for a wide range of carbon foil thickness to study the time development of the excited state populations.

  12. Microwave electron cyclotron electron resonance (ECR) ion source with a large, uniformly distributed, axially symmetric, ECR plasma volume

    DOE Patents [OSTI]

    Alton, Gerald D. (Kingston, TN)

    1996-01-01

    An electron cyclotron resonance (ECR) ion source includes a primary mirror coil disposed coaxially around a vacuum vessel in which a plasma is induced and introducing a solenoidal ECR-producing field throughout the length of the vacuum vessel. Radial plasma confinement is provided by a multi-cusp, multi-polar permanent magnet array disposed azimuthally around the vessel and within the primary mirror coil. Axial confinement is provided either by multi-cusp permanent magnets at the opposite axial ends of the vessel, or by secondary mirror coils disposed on opposite sides of the primary coil.

  13. Beam extraction and high stability operation of high current electron cyclotron resonance proton ion source

    SciTech Connect (OSTI)

    Roychowdhury, P. Mishra, L.; Kewlani, H.; Mittal, K. C.; Patil, D. S.

    2014-03-15

    A high current electron cyclotron resonance proton ion source is designed and developed for the low energy high intensity proton accelerator at Bhabha Atomic Research Centre. The plasma discharge in the ion source is stabilized by minimizing the reflected microwave power using four stub auto tuner and magnetic field. The optimization of extraction geometry is performed using PBGUNS code by varying the aperture, shape, accelerating gap, and the potential on the electrodes. While operating the source, it was found that the two layered microwave window (6 mm quartz plate and 2 mm boron nitride plate) was damaged (a fine hole was drilled) by the back-streaming electrons after continuous operation of the source for 3 h at beam current of 20–40 mA. The microwave window was then shifted from the line of sight of the back-streaming electrons and located after the water-cooled H-plane bend. In this configuration the stable operation of the high current ion source for several hours is achieved. The ion beam is extracted from the source by biasing plasma electrode, puller electrode, and ground electrode to +10 to +50 kV, ?2 to ?4 kV, and 0 kV, respectively. The total ion beam current of 30–40 mA is recorded on Faraday cup at 40 keV of beam energy at 600–1000 W of microwave power, 800–1000 G axial magnetic field and (1.2–3.9) × 10{sup ?3} mbar of neutral hydrogen gas pressure in the plasma chamber. The dependence of beam current on extraction voltage, microwave power, and gas pressure is investigated in the range of operation of the ion source.

  14. Dosimetric characterization and output verification for conical brachytherapy surface applicators. Part I. Electronic brachytherapy source

    SciTech Connect (OSTI)

    Fulkerson, Regina K. Micka, John A.; DeWerd, Larry A.

    2014-02-15

    Purpose: Historically, treatment of malignant surface lesions has been achieved with linear accelerator based electron beams or superficial x-ray beams. Recent developments in the field of brachytherapy now allow for the treatment of surface lesions with specialized conical applicators placed directly on the lesion. Applicators are available for use with high dose rate (HDR){sup 192}Ir sources, as well as electronic brachytherapy sources. Part I of this paper will discuss the applicators used with electronic brachytherapy sources; Part II will discuss those used with HDR {sup 192}Ir sources. Although the use of these applicators has gained in popularity, the dosimetric characteristics including depth dose and surface dose distributions have not been independently verified. Additionally, there is no recognized method of output verification for quality assurance procedures with applicators like these. Existing dosimetry protocols available from the AAPM bookend the cross-over characteristics of a traditional brachytherapy source (as described by Task Group 43) being implemented as a low-energy superficial x-ray beam (as described by Task Group 61) as observed with the surface applicators of interest. Methods: This work aims to create a cohesive method of output verification that can be used to determine the dose at the treatment surface as part of a quality assurance/commissioning process for surface applicators used with HDR electronic brachytherapy sources (Part I) and{sup 192}Ir sources (Part II). Air-kerma rate measurements for the electronic brachytherapy sources were completed with an Attix Free-Air Chamber, as well as several models of small-volume ionization chambers to obtain an air-kerma rate at the treatment surface for each applicator. Correction factors were calculated using MCNP5 and EGSnrc Monte Carlo codes in order to determine an applicator-specific absorbed dose to water at the treatment surface from the measured air-kerma rate. Additionally, relative dose measurements of the surface dose distributions and characteristic depth dose curves were completed in-phantom. Results: Theoretical dose distributions and depth dose curves were generated for each applicator and agreed well with the measured values. A method of output verification was created that allows users to determine the applicator-specific dose to water at the treatment surface based on a measured air-kerma rate. Conclusions: The novel output verification methods described in this work will reduce uncertainties in dose delivery for treatments with these kinds of surface applicators, ultimately improving patient care.

  15. Langmuir probe diagnostics of plasma in high current electron cyclotron resonance proton ion source

    SciTech Connect (OSTI)

    Roychowdhury, P.; Kewlani, H.; Mishra, L.; Mittal, K. C.; Patil, D. S.

    2013-07-15

    A high current Electron Cyclotron Resonance (ECR) proton ion source has been developed for low energy high intensity proton accelerator at Bhabha Atomic Research Centre. Langmuir probe diagnostics of the plasma generated in this proton ion source is performed using Langmuir probe. The diagnostics of plasma in the ion source is important as it determines beam parameters of the ion source, i.e., beam current, emittance, and available species. The plasma parameter measurement in the ion source is performed in continuously working and pulsed mode using hydrogen as plasma generation gas. The measurement is performed in the ECR zone for operating pressure and microwave power range of 10{sup ?4}–10{sup ?3} mbar and 400–1000 W. An automated Langmuir probe diagnostics unit with data acquisition system is developed to measure these parameters. The diagnostics studies indicate that the plasma density and plasma electron temperature measured are in the range 5.6 × 10{sup 10} cm{sup ?3} to 3.8 × 10{sup 11} cm{sup ?3} and 4–14 eV, respectively. Using this plasma, ion beam current of tens of mA is extracted. The variations of plasma parameters with microwave power, gas pressure, and radial location of the probe have been studied.

  16. Studies on a Q/A selector for the SECRAL electron cyclotron resonance ion source

    SciTech Connect (OSTI)

    Yang, Y., E-mail: yangyao@impcas.ac.cn [Institute of Modern Physics, CAS, Lanzhou 730000 (China); University of Chinese Academy of Sciences, CAS, Beijing 100039 (China); Sun, L. T.; Feng, Y. C.; Fang, X.; Lu, W.; Zhang, W. H.; Cao, Y.; Zhang, X. Z.; Zhao, H. W. [Institute of Modern Physics, CAS, Lanzhou 730000 (China)

    2014-08-15

    Electron cyclotron resonance ion sources are widely used in heavy ion accelerators in the world because they are capable of producing high current beams of highly charged ions. However, the design of the Q/A selector system for these devices is challenging, because it must have a sufficient ion resolution while controlling the beam emittance growth. Moreover, this system has to be matched for a wide range of ion beam species with different intensities. In this paper, research on the Q/A selector system at the SECRAL (Superconducting Electron Cyclotron Resonance ion source with Advanced design in Lanzhou) platform both in experiment and simulation is presented. Based on this study, a new Q/A selector system has been designed for SECRAL II. The features of the new design including beam simulations are also presented.

  17. An inverted cylindrical sputter magnetron as metal vapor supply for electron cyclotron resonance ion sources

    SciTech Connect (OSTI)

    Weichsel, T., E-mail: tim.weichsel@fep.fraunhofer.de; Hartung, U.; Kopte, T. [Fraunhofer Institute for Electron Beam and Plasma Technology, 01277 Dresden (Germany)] [Fraunhofer Institute for Electron Beam and Plasma Technology, 01277 Dresden (Germany); Zschornack, G. [Institute of Solid State Physics, Dresden University of Technology, 01062 Dresden, Germany and Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Ion Beam Physics and Materials Research, Dresden (Germany)] [Institute of Solid State Physics, Dresden University of Technology, 01062 Dresden, Germany and Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Ion Beam Physics and Materials Research, Dresden (Germany); Kreller, M.; Silze, A. [DREEBIT GmbH, 01900 Grossroehrsdorf (Germany)] [DREEBIT GmbH, 01900 Grossroehrsdorf (Germany)

    2014-05-15

    An inverted cylindrical sputter magnetron device has been developed. The magnetron is acting as a metal vapor supply for an electron cyclotron resonance (ECR) ion source. FEM simulation of magnetic flux density was used to ensure that there is no critical interaction between both magnetic fields of magnetron and ECR ion source. Spatially resolved double Langmuir probe and optical emission spectroscopy measurements show an increase in electron density by one order of magnitude from 1 × 10{sup 10} cm{sup ?3} to 1 × 10{sup 11} cm{sup ?3}, when the magnetron plasma is exposed to the magnetic mirror field of the ECR ion source. Electron density enhancement is also indicated by magnetron plasma emission photography with a CCD camera. Furthermore, photographs visualize the formation of a localized loss-cone - area, when the magnetron is operated at magnetic mirror field conditions. The inverted cylindrical magnetron supplies a metal atom load rate of R > 1 × 10{sup 18} atoms/s for aluminum, which meets the demand for the production of a milliampere Al{sup +} ion beam.

  18. DEVELOPMENT OF A COMPACT PHOTO-INJECTOR WITH RFFOCUSING LENS FOR SHORT PULSE ELECTRON SOURCE APPLICATION

    SciTech Connect (OSTI)

    Grabenhofer, Alexander; Eaton, Douglas W.

    2013-09-01

    For development of compact ultrafast electron source system, we are currently designing a short-pulse RF-gun with RF focusing structure by means of a series of comprehensive modeling analysis processes. EM design of a 2.5 cell resonant cavity with input coupler, acceleration dynamics of photo-emitted electron bunch, EM design of RF-lens with input coupler, and phasespace analysis of focused electron bunch are systematically examined with multi-physics simulators. All the features of the 2.856 GHz cavity geometry were precisely engineered for acceleration energies ranging from 100 keV to 500 keV (safety limited) to be powered by our 5 MW S-band klystron. The klystron (Thales TH2163) and modulator system (ScandiNova K1 turnkey system) were successfully installed and tested. Performance tests of the klystron system show peak output power > 5 MW, as per operation specifications. At the quasi-relativistic energies, the electron source is capable of generating 100fC – 1 pC electron bunch with pulse duration close to 30 fs – 1 ps and transverse size of a few hundred microns. PIC simulations have shown that the electron bunch undergoes fast RF acceleration, rapidly reaching the desired energies, which can be controlled by tuning RF injection phase and input driving power. It has been shown that it is possible to also focus/compress the bunch longitudinally using a RF-lens, which would allow us to control the temporal resolution of the system as well. While our primary analysis has been performed on a 2.5 cell design, we are also looking into half-cell (single cavity) design that is expected to provide the same range of beam energy with a simple configuration.

  19. A mulitple cathode gun design for the eRHIC polarized electron source

    SciTech Connect (OSTI)

    Chang, X.; Ben-Zvi, I.; Kewisch, J.; Litvinenko, V.; Pikin, A.; Ptitsyn, V.; Rao, T.; Sheehy, B.; Skaritka, J.; Wang, E.; Wu, Q.; Xin, T.

    2011-03-28

    The future electron-ion collider eRHIC requires a high average current ({approx}50 mA), short bunch ({approx}3 mm), low emittance ({approx}20 {micro}m) polarized electron source. The maximum average current of a polarized electron source so far is more than 1 mA, but much less than 50 mA, from a GaAs:Cs cathode. One possible approach to overcome the average current limit and to achieve the required 50 mA beam for eRHIC, is to combine beamlets from multiple cathodes to one beam. In this paper, we present the feasibility studies of this technique. The future eRHIC project, next upgrade of RHIC, will be the first electron-heavy ion collider in the world. It requires polarized electron source with a high average current ({approx}50 mA), short bunch ({approx}3 mm), emittance of about 20 {micro}m and energy spread of {approx}1% at 10 MeV. The state-of-art polarized electron cathode can generate average current of about more than 1 mA, but much less than 50 mA. The current is limited by the low quantum efficiency, space charge and ultra-high vacuum requirement of the polarized cathode. A possible approach to achieve the 50 mA beam is to employ multiple cathodes, such as 20 cathodes, and funnel the multiple bunched beams from cathodes to the same axis. Fig.1 illustrates schematically the concept of combining the multiple beams. We name it as 'Gatling gun' because it bears functional similarity to a Gatling gun. Laser beams strike the cathodes sequentially with revolution frequency of 700 kHz. Each beam bunch is focused by a solenoid and is bent toward the combiner. The combiner with rotating bending field bends all bunches arriving the combiner with a rotational pattern to the same axis. The energy of each bunch is modified by a bunching cavity (112MHz) and a 3rd harmonic cavity (336MHz). The bunch length is compressed ballistically in the drift space and is frozen after energy has been boosted to 10 MeV by the Booster linac. Each beam bunch contains 3.5 nC charge. The space charge is very strong at energy of 200 keV. A long bunch, {sigma} of 250 ps, is adopted to reduce the space charge on cathode. To compress the beam to final length of 3 mm (10 ps) can be achieved by ballistic compression with a 3rd harmonic cavity.

  20. Estimation of the electron density and radiative energy losses in a calcium plasma source based on an electron cyclotron resonance discharge

    SciTech Connect (OSTI)

    Potanin, E. P. Ustinov, A. L.

    2013-06-15

    The parameters of a calcium plasma source based on an electron cyclotron resonance (ECR) discharge were calculated. The analysis was performed as applied to an ion cyclotron resonance system designed for separation of calcium isotopes. The plasma electrons in the source were heated by gyrotron microwave radiation in the zone of the inhomogeneous magnetic field. It was assumed that, in such a combined trap, the energy of the extraordinary microwave propagating from the high-field side was initially transferred to a small group of resonance electrons. As a result, two electron components with different transverse temperatures-the hot resonance component and the cold nonresonance component-were created in the plasma. The longitudinal temperatures of both components were assumed to be equal. The entire discharge space was divided into a narrow ECR zone, where resonance electrons acquired transverse energy, and the region of the discharge itself, where the gas was ionized. The transverse energy of resonance electrons was calculated by solving the equations for electron motion in an inhomogeneous magnetic field. Using the law of energy conservation and the balance condition for the number of hot electrons entering the discharge zone and cooled due to ionization and elastic collisions, the density of hot electrons was estimated and the dependence of the longitudinal temperature T{sub e Parallel-To} of the main (cold) electron component on the energy fraction {beta} lost for radiation was obtained.

  1. Rotatable spin-polarized electron source for inverse-photoemission experiments

    SciTech Connect (OSTI)

    Stolwijk, S. D. Wortelen, H.; Schmidt, A. B.; Donath, M.

    2014-01-15

    We present a ROtatable Spin-polarized Electron source (ROSE) for the use in spin- and angle-resolved inverse-photoemission (SR-IPE) experiments. A key feature of the ROSE is a variable direction of the transversal electron beam polarization. As a result, the inverse-photoemission experiment becomes sensitive to two orthogonal in-plane polarization directions, and, for nonnormal electron incidence, to the out-of-plane polarization component. We characterize the ROSE and test its performance on the basis of SR-IPE experiments. Measurements on magnetized Ni films on W(110) serve as a reference to demonstrate the variable spin sensitivity. Moreover, investigations of the unoccupied spin-dependent surface electronic structure of Tl/Si(111) highlight the capability to analyze complex phenomena like spin rotations in momentum space. Essentially, the ROSE opens the way to further studies on complex spin-dependent effects in the field of surface magnetism and spin-orbit interaction at surfaces.

  2. Numerical simulation of ion charge breeding in electron beam ion source

    SciTech Connect (OSTI)

    Zhao, L., E-mail: zhao@far-tech.com; Kim, Jin-Soo [FAR-TECH, Inc., San Diego, California 92122 (United States)] [FAR-TECH, Inc., San Diego, California 92122 (United States)

    2014-02-15

    The Electron Beam Ion Source particle-in-cell code (EBIS-PIC) tracks ions in an EBIS electron beam while updating electric potential self-consistently and atomic processes by the Monte Carlo method. Recent improvements to the code are reported in this paper. The ionization module has been improved by using experimental ionization energies and shell effects. The acceptance of injected ions and the emittance of extracted ion beam are calculated by extending EBIS-PIC to the beam line transport region. An EBIS-PIC simulation is performed for a Cs charge-breeding experiment at BNL. The charge state distribution agrees well with experiments, and additional simulation results of radial profiles and velocity space distributions of the trapped ions are presented.

  3. Electron-beam-ion-source (EBIS) modeling progress at FAR-TECH, Inc

    SciTech Connect (OSTI)

    Kim, J. S. Zhao, L. Spencer, J. A. Evstatiev, E. G.

    2015-01-09

    FAR-TECH, Inc. has been developing a numerical modeling tool for Electron-Beam-Ion-Sources (EBISs). The tool consists of two codes. One is the Particle-Beam-Gun-Simulation (PBGUNS) code to simulate a steady state electron beam and the other is the EBIS-Particle-In-Cell (EBIS-PIC) code to simulate ion charge breeding with the electron beam. PBGUNS, a 2D (r,z) electron gun and ion source simulation code, has been extended for efficient modeling of EBISs and the work was presented previously. EBIS-PIC is a space charge self-consistent PIC code and is written to simulate charge breeding in an axisymmetric 2D (r,z) device allowing for full three-dimensional ion dynamics. This 2D code has been successfully benchmarked with Test-EBIS measurements at Brookhaven National Laboratory. For long timescale (< tens of ms) ion charge breeding, the 2D EBIS-PIC simulations take a long computational time making the simulation less practical. Most of the EBIS charge breeding, however, may be modeled in 1D (r) as the axial dependence of the ion dynamics may be ignored in the trap. Where 1D approximations are valid, simulations of charge breeding in an EBIS over long time scales become possible, using EBIS-PIC together with PBGUNS. Initial 1D results are presented. The significance of the magnetic field to ion dynamics, ion cooling effects due to collisions with neutral gas, and the role of Coulomb collisions are presented.

  4. Facility for fast neutron irradiation tests of electronics at the ISIS spallation neutron source

    SciTech Connect (OSTI)

    Andreani, C.; Pietropaolo, A.; Salsano, A.; Gorini, G.; Tardocchi, M.; Paccagnella, A.; Gerardin, S.; Frost, C. D.; Ansell, S.; Platt, S. P.

    2008-03-17

    The VESUVIO beam line at the ISIS spallation neutron source was set up for neutron irradiation tests in the neutron energy range above 10 MeV. The neutron flux and energy spectrum were shown, in benchmark activation measurements, to provide a neutron spectrum similar to the ambient one at sea level, but with an enhancement in intensity of a factor of 10{sup 7}. Such conditions are suitable for accelerated testing of electronic components, as was demonstrated here by measurements of soft error rates in recent technology field programable gate arrays.

  5. Philips Light Sources & Electronics is Developing an Efficient, Smaller, Cost-Effective Family of LED Drivers

    Broader source: Energy.gov [DOE]

    With the help of DOE funding, Philips Light Sources & Electronics is developing a new family of LED drivers that are more efficient and cost-effective as well as smaller in size than currently available drivers. The new drivers are switch-mode power supplies that are similar to today's drivers, but with an improved design. In addition, they have a different topology—boost plus LLC—for wattages of 40W and above, but they retain the commonly used flyback topology at lower wattages.

  6. Design and testing of an electron cyclotron resonance heating ion source for use in high field compact superconducting cyclotrons

    E-Print Network [OSTI]

    Artz, Mark E

    2012-01-01

    The main goal of this project is to evaluate the feasibility of axial injection of a high brightness beam from an Electron Cyclotron Resonance ion source into a high magnetic field cyclotron. Axial injection from an ion ...

  7. The electron cyclotron resonance ion source with arc-shaped coils concept (invited)

    SciTech Connect (OSTI)

    Koivisto, H.; Tarvainen, O.; Suominen, P.; Spaedtke, P.

    2012-02-15

    The main limitation to further improve the performance of ECR ion sources is set by the magnet technology related to the multipole magnet field used for the closed minimum-B structure. The JYFL ion source group has sought different approaches to improve the strength of the minimum-B structure required for the production of highly charged ion beams. It was found out that such a configuration can be realized with arc shaped coils. The first prototype, electron cyclotron resonance ion source with arc-shaped coils (ARC-ECRIS), was constructed and tested at JYFL in 2006. It was confirmed that such an ion source can be used for the production of highly charged ion beams. Regardless of several cost-driven compromises such as extraction mirror ratio of 1.05-1.2, microwave frequency of 6.4 GHz, and beam line with limited capacity, Ar{sup 4+} beam intensity of up to 2 {mu}A was measured. Subsequent design study has shown that the ARC-ECRIS operating at the microwave frequency above 40 GHz could be constructed. This specific design would be based on NbTi-wires and it fulfills the experimental magnetic field scaling laws. In this article, the ARC-ECRIS concept and its potential applications will be described.

  8. Experiment study of an electron cyclotron resonant ion source based on a tapered resonance cavity

    SciTech Connect (OSTI)

    Yang, Juan; Shi, Feng; Jin, Yizhou; Wang, Yunmin [College of Astronautics, Northwestern Polytechnic University, Xi'an, Shaanxi 710072 (China)] [College of Astronautics, Northwestern Polytechnic University, Xi'an, Shaanxi 710072 (China); Komurasaki, Kimiya [Department of Aeronautics and Astronautics, The University of Tokyo, Hongo 7-3-1, Bunkyo, Tokyo 113-8656 (Japan)] [Department of Aeronautics and Astronautics, The University of Tokyo, Hongo 7-3-1, Bunkyo, Tokyo 113-8656 (Japan)

    2013-12-15

    Electron cyclotron resonant plasma is one type of magnetised plasma generated by continuous microwave energy. It has the property of high degree of ionization and large volume at low gas pressure, which makes it useful for space propulsion and material processing. This article presents the experiment study of the plasma properties and ion beam extraction from an electron cyclotron resonant ion source based on a tapered resonance cavity. Optical emission spectroscopy based on a simple collisional radiation model was used for plasma diagnosis. Experiment results show that, at microwave power setting ranging from 7.06 to 17.40 W and mass flow rate ranging from 1 to 10 sccm, argon gas can be ionized. Ion beam of 109.1 mA from the ion source can be extracted at microwave power of 30 W, mass flow rate of 10 sccm, and accel voltage of 800 V. The diagnosed plasma temperature and density are 2.4–5.2 eV and 2 × 10{sup 16}–4.8 × 10{sup 17} m{sup ?3}, respectively.

  9. Cosmic ray electron anisotropies as a tool to discriminate between exotic and astrophysical sources

    E-Print Network [OSTI]

    Cernuda, Ignacio

    2009-01-01

    Recent results from the PAMELA, ATIC, PPB BETS and Fermi collaborations extend the energy range in the electron flux measurement up to unexplored energies in the hundred GeVs range confirming the bump starting at about 10GeV already suggested by HEAT and AMS01 data . This bump can be explained by annihilating dark matter in the context of exotic physics, or by nearby astrophysical sources e.g. pulsars. In order to discriminate between competing models for primary positron production, the study of anisotropies ,complementary to the spectrum determination, shows up as new tool to look for the origin of the lepton excess. In this letter we calculate the contribution to the electron flux given by the collection of all known gamma ray pulsars (as listed in the ATNF catalogue) and by annihilating dark matter both in case of a clumpy halo or in case the excess can be atributed to a nearby sizeable dark matter clump. We address the problem of the electron anisotropy in both scenarios and estimate the prospect that a ...

  10. Electron Beam Energy Chirp Control with a Rectangular Corrugated Structure at the Linac Coherent Light Source

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zhang, Zhen; Bane, Karl; Ding, Yantao; Huang, Zhirong; Iverson, Richard; Maxwell, Timothy; Stupakov, Gennady; Wang, Lanfa

    2015-01-30

    Electron beam energy chirp is an important parameter that affects the bandwidth and performance of a linac-based, free-electron laser. In this paper we study the wakefields generated by a beam passing between at metallic plates with small corrugations, and then apply such a device as a passive dechirper for the Linac Coherent Light Source (LCLS) energy chirp control with a multi-GeV and femtosecond electron beam. Similar devices have been tested in several places at relatively low energies (#24;100 MeV) and with relatively long bunches (> 1ps). In the parameter regime of the LCLS dechirper, with the corrugation size similar to the gap between the plates, the analytical solutions of the wakefields are no longer applicable, and we resort to a #12;field matching program to obtain the wakes. Based on the numerical calculations, we #12;fit the short-range, longitudinal wakes to simple formulas, valid over a large, useful parameter range. Finally, since the transverse wakefields - both dipole and quadrupole-are strong, we compute and include them in beam dynamics simulations to investigate the error tolerances when this device is introduced in the LCLS.

  11. Electron Beam Energy Chirp Control with a Rectangular Corrugated Structure at the Linac Coherent Light Source

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zhang, Zhen; Bane, Karl; Ding, Yantao; Huang, Zhirong; Iverson, Richard; Maxwell, Timothy; Stupakov, Gennady; Wang, Lanfa

    2015-01-30

    Electron beam energy chirp is an important parameter that affects the bandwidth and performance of a linac-based, free-electron laser. In this paper we study the wakefields generated by a beam passing between at metallic plates with small corrugations, and then apply such a device as a passive dechirper for the Linac Coherent Light Source (LCLS) energy chirp control with a multi-GeV and femtosecond electron beam. Similar devices have been tested in several places at relatively low energies (#24;100 MeV) and with relatively long bunches (> 1ps). In the parameter regime of the LCLS dechirper, with the corrugation size similar tomore »the gap between the plates, the analytical solutions of the wakefields are no longer applicable, and we resort to a #12;field matching program to obtain the wakes. Based on the numerical calculations, we #12;fit the short-range, longitudinal wakes to simple formulas, valid over a large, useful parameter range. Finally, since the transverse wakefields - both dipole and quadrupole-are strong, we compute and include them in beam dynamics simulations to investigate the error tolerances when this device is introduced in the LCLS.« less

  12. Measurements of plasma bremsstrahlung and plasma energy density produced by electron cyclotron resonance ion source plasmas

    E-Print Network [OSTI]

    Noland, Jonathan David

    2011-01-01

    as function of time. Right: electron energy as function ofas function of time. Right: electron energy as function ofas function of time. Right: electron energy as function of

  13. Time-resolved soft-x-ray studies of energy transport in layered and planar laser-driven targets

    SciTech Connect (OSTI)

    Stradling, G.L.

    1982-04-19

    New low-energy x-ray diagnostic techniques are used to explore energy-transport processes in laser heated plasmas. Streak cameras are used to provide 15-psec time-resolution measurements of subkeV x-ray emission. A very thin (50 ..mu..g/cm/sup 2/) carbon substrate provides a low-energy x-ray transparent window to the transmission photocathode of this soft x-ray streak camera. Active differential vacuum pumping of the instrument is required. The use of high-sensitivity, low secondary-electron energy-spread CsI photocathodes in x-ray streak cameras is also described. Significant increases in sensitivity with only a small and intermittant decrease in dynamic range were observed. These coherent, complementary advances in subkeV, time-resolved x-ray diagnostic capability are applied to energy-transport investigations of 1.06-..mu..m laser plasmas. Both solid disk targets of a variety of Z's as well as Be-on-Al layered-disk targets were irradiated with 700-psec laser pulses of selected intensity between 3 x 10/sup 14/ W/cm/sup 2/ and 1 x 10/sup 15/ W/cm/sup 2/.

  14. Non-ambipolar radio-frequency plasma electron source and systems and methods for generating electron beams

    DOE Patents [OSTI]

    Hershkowitz, Noah (Madison, WI); Longmier, Benjamin (Madison, WI); Baalrud, Scott (Madison, WI)

    2009-03-03

    An electron generating device extracts electrons, through an electron sheath, from plasma produced using RF fields. The electron sheath is located near a grounded ring at one end of a negatively biased conducting surface, which is normally a cylinder. Extracted electrons pass through the grounded ring in the presence of a steady state axial magnetic field. Sufficiently large magnetic fields and/or RF power into the plasma allow for helicon plasma generation. The ion loss area is sufficiently large compared to the electron loss area to allow for total non-ambipolar extraction of all electrons leaving the plasma. Voids in the negatively-biased conducting surface allow the time-varying magnetic fields provided by the antenna to inductively couple to the plasma within the conducting surface. The conducting surface acts as a Faraday shield, which reduces any time-varying electric fields from entering the conductive surface, i.e. blocks capacitive coupling between the antenna and the plasma.

  15. REX, a 5-MV pulsed-power source for driving high-brightness electron beam diodes

    SciTech Connect (OSTI)

    Carlson, R.L.; Kauppila, T.J.; Ridlon, R.N.

    1991-01-01

    The Relativistic Electron-beam Experiment, or REX accelerator, is a pulsed-power source capable of driving a 100-ohm load at 5 MV, 50 kA, 45 ns (FWHM) with less than a 10-ns rise and 15-ns fall time. This paper describes the pulsed-power modifications, modelling, and extensive measurements on REX to allow it to drive high impedance (100s of ohms) diode loads with a shaped voltage pulse. A major component of REX is the 1.83-m-diam {times} 25.4-cm-thick Lucite insulator with embedded grading rings that separates the output oil transmission line from the vacuum vessel that contains the re-entrant anode and cathode assemblies. A radially tailored, liquid-based resistor provides a stiff voltage source that is insensitive to small variations of the diode current and, in addition, optimizes the electric field stress across the vacuum side of the insulator. The high-current operation of REX employs both multichannel peaking and point-plane diverter switches. This mode reduces the prepulse to less than 2 kV and the postpulse to less than 5% of the energy delivered to the load. Pulse shaping for the present diode load is done through two L-C transmission line filters and a tapered, glycol-based line adjacent to the water PFL and output switch. This has allowed REX to drive a diode producing a 4-MV, 4.5-kA, 55-ns flat-top electron beam with a normalized Lapostolle emittance of 0.96 mm-rad corresponding to a beam brightness in excess of 4.4 {times} 10{sup 8} A/m{sup 2} {minus}rad{sup 2}. 6 refs., 13 figs.

  16. Direct laser acceleration of electrons in free-space

    E-Print Network [OSTI]

    Carbajo, Sergio; Wong, Liang Jie; Miller, R J Dwayne; Kärtner, Franz X

    2015-01-01

    Compact laser-driven accelerators are versatile and powerful tools of unarguable relevance on societal grounds for the diverse purposes of science, health, security, and technology because they bring enormous practicality to state-of-the-art achievements of conventional radio-frequency accelerators. Current benchmarking laser-based technologies rely on a medium to assist the light-matter interaction, which impose material limitations or strongly inhomogeneous fields. The advent of few cycle ultra-intense radially polarized lasers has materialized an extensively studied novel accelerator that adopts the simplest form of laser acceleration and is unique in requiring no medium to achieve strong longitudinal energy transfer directly from laser to particle. Here we present the first observation of direct longitudinal laser acceleration of non-relativistic electrons that undergo highly-directional multi-GeV/m accelerating gradients. This demonstration opens a new frontier for direct laser-driven particle accelerati...

  17. Fast and efficient charge breeding of the Californium rare isotope breeder upgrade electron beam ion source

    SciTech Connect (OSTI)

    Ostroumov, P. N.; Barcikowski, A.; Dickerson, C. A.; Perry, A.; Pikin, A. I.; Sharamentov, S. I.; Vondrasek, R. C.; Zinkann, G. P.

    2015-08-28

    The Electron Beam Ion Source (EBIS), developed to breed Californium Rare Isotope Breeder Upgrade (CARIBU) radioactive beams at Argonne Tandem Linac Accelerator System (ATLAS), is being tested off-line. A unique property of the EBIS is a combination of short breeding times, high repetition rates, and a large acceptance. Overall, we have implemented many innovative features during the design and construction of the CARIBU EBIS as compared to the existing EBIS breeders. The off-line charge breeding tests are being performed using a surface ionization source that produces singly charged cesium ions. The main goal of the off-line commissioning is to demonstrate stable operation of the EBIS at a 10 Hz repetition rate and a breeding efficiency into single charge state higher than 15%. These goals have been successfully achieved and exceeded. We have measured (20% ± 0.7%) breeding efficiency into the single charge state of 28+ cesium ions with the breeding time of 28 ms. In general, the current CARIBU EBIS operational parameters can provide charge breeding of any ions in the full mass range of periodic table with high efficiency, short breeding times, and sufficiently low charge-to-mass ratio, 1/6.3 for the heaviest masses, for further acceleration in ATLAS. In this study, we discuss the parameters of the EBIS and the charge breeding results in a pulsed injection mode with repetition rates up to 10 Hz.

  18. Fast and efficient charge breeding of the Californium rare isotope breeder upgrade electron beam ion source

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ostroumov, P. N.; Barcikowski, A.; Dickerson, C. A.; Perry, A.; Pikin, A. I.; Sharamentov, S. I.; Vondrasek, R. C.; Zinkann, G. P.

    2015-08-28

    The Electron Beam Ion Source (EBIS), developed to breed Californium Rare Isotope Breeder Upgrade (CARIBU) radioactive beams at Argonne Tandem Linac Accelerator System (ATLAS), is being tested off-line. A unique property of the EBIS is a combination of short breeding times, high repetition rates, and a large acceptance. Overall, we have implemented many innovative features during the design and construction of the CARIBU EBIS as compared to the existing EBIS breeders. The off-line charge breeding tests are being performed using a surface ionization source that produces singly charged cesium ions. The main goal of the off-line commissioning is to demonstratemore »stable operation of the EBIS at a 10 Hz repetition rate and a breeding efficiency into single charge state higher than 15%. These goals have been successfully achieved and exceeded. We have measured (20% ± 0.7%) breeding efficiency into the single charge state of 28+ cesium ions with the breeding time of 28 ms. In general, the current CARIBU EBIS operational parameters can provide charge breeding of any ions in the full mass range of periodic table with high efficiency, short breeding times, and sufficiently low charge-to-mass ratio, 1/6.3 for the heaviest masses, for further acceleration in ATLAS. In this study, we discuss the parameters of the EBIS and the charge breeding results in a pulsed injection mode with repetition rates up to 10 Hz.« less

  19. Effect of non-uniform electron energy distribution function on plasma production in large arc driven negative ion source

    SciTech Connect (OSTI)

    Shibata, T.; Koga, S.; Terasaki, R.; Hatayama, A.; Inoue, T.; Dairaku, M.; Kashiwagi, M.; Taniguchi, M.; Tobari, H.; Tsuchida, K.; Umeda, N.; Watanabe, K.

    2012-02-15

    Spatially non-uniform electron energy distribution function (EEDF) in an arc driven negative ion source (JAEA 10A negative ion source: 10 A NIS) is calculated numerically by a three-dimensional Monte Carlo kinetic model for electrons to understand spatial distribution of plasma production (such as atomic and ionic hydrogen (H{sup 0}/H{sup +}) production) in source chamber. The local EEDFs were directly calculated from electron orbits including electromagnetic effects and elastic/inelastic collision forces. From the EEDF, spatial distributions of H{sup 0}/H{sup +} production rate were obtained. The results suggest that spatial non-uniformity of H{sup 0}/H{sup +} productions is enhanced by high energy component of EEDF.

  20. Effect of magnetic-field configuration on the beam intensity from electron cyclotron resonance ion source and RIKEN superconducting electron cyclotron resonance ion source

    SciTech Connect (OSTI)

    Nakagawa, T.; Higurashi, Y.; Kidera, M.; Aihara, T.; Kase, M.; Goto, A.; Yano, Y. [RIKEN, Hirosawa 2-1, Wako, Saitama 351-0198 (Japan); SAS Ltd., Kita-shinagawa 5-9-11, Shinjuku-ku, Tokyo (Japan); RIKEN, Hirosawa 2-1, Wako, Saitama 351-0198 (Japan)

    2006-03-15

    We measured the main plasma parameters (density of electron, temperature of electrons, and ion confinement time) as a function of B{sub min} and B{sub inj} with laser ablation technique. We observed that the B{sub min} mainly affects the temperature and density of electrons and all of the three parameters increase with increasing the B{sub inj}. We also observed that the gas pressure of the plasma chamber at the rf injection side became minimum at the optimum value for B{sub min} at fixed gas flow. This result indicates that the ionization efficiency becomes maximum at optimum value for B{sub min}. From these results, it is concluded that the plasma production is strongly dependent on the B{sub min} (plasma generator). We also observed that the B{sub inj} affects the ion confinement time, temperature, and density of electrons. All of the three parameters increase with increasing B{sub inj}.

  1. Laser-driven flyer plate

    SciTech Connect (OSTI)

    Paisley, Dennis L.

    1991-01-01

    Apparatus for producing high velocity flyer plates involving placing a layer of dielectric material between a first metal foil and a second metal foil. With laser irradiation through an optical substrate, the first metal foil forms a plasma in the area of the irradiation, between the substrate and the solid portion of the first metal foil. When the pressure between the substrate and the foil reaches the stress limit of the dielectric, the dielectric will break away and launch the flyer plate out of the second metal foil. The mass of the flyer plate is controlled, as no portion of the flyer plate is transformed into a plasma.

  2. Laser-driven flyer plate

    SciTech Connect (OSTI)

    Paisley, D.L.

    1991-09-10

    Disclosed is an apparatus for producing high velocity flyer plates involving placing a layer of dielectric material between a first metal foil and a second metal foil. With laser irradiation through an optical substrate, the first metal foil forms a plasma in the area of the irradiation, between the substrate and the solid portion of the first metal foil. When the pressure between the substrate and the foil reaches the stress limit of the dielectric, the dielectric will break away and launch the flyer plate out of the second metal foil. The mass of the flyer plate is controlled, as no portion of the flyer plate is transformed into a plasma. 2 figures.

  3. Recent development of RIKEN 28 GHz superconducting electron cyclotron resonance ion source

    SciTech Connect (OSTI)

    Higurashi, Y. Ohnishi, J.; Ozeki, K.; Kidera, M.; Nakagawa, T.

    2014-02-15

    Over the past two years, we have tried to improve the performance of the RIKEN superconducting electron cyclotron resonance ion source using several methods. For the production of U vapor, we chose the sputtering method because it is possible to install a large amount of material inside the plasma chamber and thus achieve long-term operation without a break, although it is assumed that the beam intensity is weaker than in the oven technique. We also used an aluminum chamber instead of a stainless steel one. Using these methods, we successfully produced ?180 e?A of U{sup 35+} and ?230 e?A of U{sup 33+} at the injected radio frequency (RF) power of ?4 kW (28 GHz). Very recently, to further increase the beam intensity of U{sup 35+}, we have started to develop a high temperature oven and have successfully produced a highly charged U ion beam. In this contribution, we report on the beam intensity of highly charged U ions as a function of various parameters (RF power and sputtering voltage) and discuss the effects of these parameters on the beam stability in detail.

  4. Module No: 410320Electronic Transactions LawModule Title: Co-requisite:Sources of ObligationsPre-requisite

    E-Print Network [OSTI]

    Module No: 410320Electronic Transactions LawModule Title: Co-requisite:Sources of ObligationsPre-requisite: Module Type: specialization elective requirementModule level: Third year Evening StudyDaytime Study Office Phone Academic rank Instructor Name E-mailOffice Number Office Phone Academic rank Module

  5. ELECTRON FLUX SPECTRAL IMAGING OF SOLAR FLARES THROUGH REGULARIZED ANALYSIS OF HARD X-RAY SOURCE VISIBILITIES

    E-Print Network [OSTI]

    Piana, Michele

    ELECTRON FLUX SPECTRAL IMAGING OF SOLAR FLARES THROUGH REGULARIZED ANALYSIS OF HARD X-RAY SOURCE a new method for imaging spectroscopy analysis of hard X-ray emission during solar flares. The method the method to a solar flare observed on 2002 February 20 by the RHESSI instrument. The event is characterized

  6. Development of a compact thermal lithium atom beam source for measurements of electron velocity distribution function anisotropy in electron cyclotron resonance plasmas

    SciTech Connect (OSTI)

    Nishioka, T.; Shikama, T.; Nagamizo, S.; Fujii, K.; Hasuo, M. [Department of Mechanical Engineering and Science, Graduate School of Engineering, Kyoto University, Kyoto 615-8540 (Japan)] [Department of Mechanical Engineering and Science, Graduate School of Engineering, Kyoto University, Kyoto 615-8540 (Japan); Zushi, H. [Research Institute for Applied Mechanics, Kyushu University, Fukuoka 816-8580 (Japan)] [Research Institute for Applied Mechanics, Kyushu University, Fukuoka 816-8580 (Japan); Uchida, M.; Tanaka, H.; Maekawa, T. [Department of Fundamental Energy Science, Graduate School of Energy Science, Kyoto University, Kyoto 606-8502 (Japan)] [Department of Fundamental Energy Science, Graduate School of Energy Science, Kyoto University, Kyoto 606-8502 (Japan); Iwamae, A. [Research Center for Development of Far-Infrared Region, Fukui University, Fukui 910-8507 (Japan)] [Research Center for Development of Far-Infrared Region, Fukui University, Fukui 910-8507 (Japan)

    2013-07-15

    The anisotropy of the electron velocity distribution function (EVDF) in plasmas can be deduced from the polarization of emissions induced by anisotropic electron-impact excitation. In this paper, we develop a compact thermal lithium atom beam source for spatially resolved measurements of the EVDF anisotropy in electron cyclotron resonance (ECR) plasmas. The beam system is designed such that the ejected beam has a slab shape, and the beam direction is variable. The divergence and flux of the beam are evaluated by experiments and calculations. The developed beam system is installed in an ECR plasma device with a cusp magnetic field, and the LiI 2s–2p emission (670.8 nm) is observed in low-pressure helium plasma. The two-dimensional distributions of the degree and direction of the polarization in the LiI emission are measured by a polarization imaging system. The evaluated polarization distribution suggests the spatial variation of the EVDF anisotropy.

  7. Studies of Charge Exchange in a High?Pressure Pulsed Electron Impact Source

    E-Print Network [OSTI]

    Sharma, D. K. Sen; Hierl, Peter M.; Franklin, J. L.

    1972-01-01

    A high pressure pulsed ion source has been used in a time?of?flight mass spectrometer in order to study the charge exchangereactions in Ar–H2 and Ar–D2 systems using the ion source in the ?ermák mode of operation. As the source was used in a pulsed...

  8. Light Well: ATunable Free-Electron Light Source on a Chip K. F. MacDonald,1,* Y. H. Fu,2

    E-Print Network [OSTI]

    Zheludev, Nikolay

    Light Well: ATunable Free-Electron Light Source on a Chip G. Adamo,1 K. F. MacDonald,1,* Y. H. Fu,2 metal-dielectric structure creates a new type of tunable, nanoscale radiation source--a ``light well''. In the reported demonstration, tunable light is generated at an intensity of $200 W=cm2 as electrons with energies

  9. Wakefield acceleration in atmospheric plasmas: a possible source of MeV electrons

    E-Print Network [OSTI]

    Arrayás, M; Seviour, R; Trueba, J L

    2015-01-01

    Intense electromagnetic pulses interacting with a plasma can create a wake of plasma oscillations. Electrons trapped in such oscillations can be accelerated under certain conditions to very high energies. We study the conditions for the wakefield acceleration to produce MeV electrons in atmospheric plasmas. This mechanism may explain the origin of MeV or runaway electrons needed in the current theories for the production of Terrestrial Gamma ray Flashes.

  10. Operation of an ungated diamond field-emission array cathode in a L-band radiofrequency electron source

    SciTech Connect (OSTI)

    Piot, P. [Northern Illinois Center for Accelerator and Detector Development and Department of Physics, Northern Illinois University, DeKalb, Illinois 60115 (United States); Accelerator Physics Center, Fermi National Accelerator Laboratory, Batavia, Illinois 60510 (United States); Brau, C. A.; Gabella, W. E.; Ivanov, B.; Mendenhall, M. H. [Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee 37235 (United States); Choi, B. K. [Department of Electrical Engineering and Computer Science, Vanderbilt University, Nashville, Tennessee 37235 (United States); Vanderbilt Institute of Nanoscale Science and Engineering, Vanderbilt University, Nashville, Tennessee 37235 (United States); Blomberg, B.; Mihalcea, D.; Panuganti, H. [Northern Illinois Center for Accelerator and Detector Development and Department of Physics, Northern Illinois University, DeKalb, Illinois 60115 (United States); Jarvis, J. [Advanced Energy Systems, Inc., Medford, New York 11763 (United States); Prieto, P.; Reid, J. [Accelerator Division, Fermi National Accelerator Laboratory, Batavia, Illinois 60510 (United States)

    2014-06-30

    We report on the operation of a field-emitter-array cathode in a conventional L-band radio-frequency electron source. The cathode consisted of an array of ?10{sup 6} diamond tips on pyramids. Maximum current on the order of 15?mA was reached and the cathode did not show appreciable signs of fatigue after weeks of operation. The measured Fowler-Nordheim characteristics, transverse beam density, and current stability are discussed.

  11. Effect of the plasma instability on the beam intensity from RIKEN 18 GHz electron cyclotron resonance ion source

    SciTech Connect (OSTI)

    Higurashi, Y.; Nakagawa, T.; Kidera, M.; Aihara, T.; Kobayashi, K.; Kase, M.; Goto, A.; Yano, Y. [RIKEN, Hirosawa 2-1, Wako, Saitama 351-0198 (Japan); SAS Ltd., Kita-shinagawa 5-9-11, Shinjuku-ku, Tokyo (Japan); RIKEN, Hirosawa 2-1, Wako, Saitama 351-0198 (Japan)

    2006-03-15

    We measured the beam oscillation of RIKEN 18 GHz electron cyclotron resonance ion source for various conditions. In this experiment, the frequency of the beam oscillation increases with increasing the gas pressure and decreases with increasing rf power. The oscillation frequency is strongly dependent on the negative voltage of biased disk, i.e., the frequency increases with increasing the negative voltage. We observed that the frequency is strongly dependent on the mass of ionized gas.

  12. Accelerator-based neutron source using a cold deuterium target with degenerate electrons

    SciTech Connect (OSTI)

    Phillips, R. E.; Ordonez, C. A. [Department of Physics, University of North Texas, Denton, Texas 76203 (United States)] [Department of Physics, University of North Texas, Denton, Texas 76203 (United States)

    2013-07-15

    A neutron generator is considered in which a beam of tritons is incident on a hypothetical cold deuterium target with degenerate electrons. The energy efficiency of neutron generation is found to increase substantially with electron density. Recent reports of potential targets are discussed.

  13. Coherent electron cooling

    SciTech Connect (OSTI)

    Litvinenko,V.

    2009-05-04

    Cooling intense high-energy hadron beams remains a major challenge in modern accelerator physics. Synchrotron radiation is still too feeble, while the efficiency of two other cooling methods, stochastic and electron, falls rapidly either at high bunch intensities (i.e. stochastic of protons) or at high energies (e-cooling). In this talk a specific scheme of a unique cooling technique, Coherent Electron Cooling, will be discussed. The idea of coherent electron cooling using electron beam instabilities was suggested by Derbenev in the early 1980s, but the scheme presented in this talk, with cooling times under an hour for 7 TeV protons in the LHC, would be possible only with present-day accelerator technology. This talk will discuss the principles and the main limitations of the Coherent Electron Cooling process. The talk will describe the main system components, based on a high-gain free electron laser driven by an energy recovery linac, and will present some numerical examples for ions and protons in RHIC and the LHC and for electron-hadron options for these colliders. BNL plans a demonstration of the idea in the near future.

  14. Measurements of plasma bremsstrahlung and plasma energy density produced by electron cyclotron resonance ion source plasmas

    E-Print Network [OSTI]

    Noland, Jonathan David

    2011-01-01

    of x-ray power and plasma energy density with microwaveof diamagnetic loop used for plasma energy density mea-the average electron energy and density. During the slowly

  15. A double-layer based model of ion confinement in electron cyclotron resonance ion source

    SciTech Connect (OSTI)

    Mascali, D. Neri, L.; Celona, L.; Castro, G.; Gammino, S.; Ciavola, G.; Torrisi, G.; Università Mediterranea di Reggio Calabria, Dipartimento di Ingegneria dell’Informazione, delle Infrastrutture e dell’Energia Sostenibile, Via Graziella, I-89100 Reggio Calabria ; Sorbello, G.; Università degli Studi di Catania, Dipartimento di Ingegneria Elettrica Elettronica ed Informatica, Viale Andrea Doria 6, 95125 Catania

    2014-02-15

    The paper proposes a new model of ion confinement in ECRIS, which can be easily generalized to any magnetic configuration characterized by closed magnetic surfaces. Traditionally, ion confinement in B-min configurations is ascribed to a negative potential dip due to superhot electrons, adiabatically confined by the magneto-static field. However, kinetic simulations including RF heating affected by cavity modes structures indicate that high energy electrons populate just a thin slab overlapping the ECR layer, while their density drops down of more than one order of magnitude outside. Ions, instead, diffuse across the electron layer due to their high collisionality. This is the proper physical condition to establish a double-layer (DL) configuration which self-consistently originates a potential barrier; this “barrier” confines the ions inside the plasma core surrounded by the ECR surface. The paper will describe a simplified ion confinement model based on plasma density non-homogeneity and DL formation.

  16. Field-Emission Properties in the ERL-Electron Source Vaibhav Kukreja

    E-Print Network [OSTI]

    Hoffstaetter, Georg

    the guidance of C. Sinclair, a similar experimental chamber was built at the Laboratory for Elementary Particle Physics (LEPP) at Cornell University for our tests. Along with the physical design of the test chamber AND HISTORY Electron Field Emission or Fowler-Nordheim quantum mechanical tunneling is the pro- cess

  17. Property-close source separation of hazardous waste and waste electrical and electronic equipment - A Swedish case study

    SciTech Connect (OSTI)

    Bernstad, Anna; Cour Jansen, Jes la; Aspegren, Henrik

    2011-03-15

    Through an agreement with EEE producers, Swedish municipalities are responsible for collection of hazardous waste and waste electrical and electronic equipment (WEEE). In most Swedish municipalities, collection of these waste fractions is concentrated to waste recycling centres where households can source-separate and deposit hazardous waste and WEEE free of charge. However, the centres are often located on the outskirts of city centres and cars are needed in order to use the facilities in most cases. A full-scale experiment was performed in a residential area in southern Sweden to evaluate effects of a system for property-close source separation of hazardous waste and WEEE. After the system was introduced, results show a clear reduction in the amount of hazardous waste and WEEE disposed of incorrectly amongst residual waste or dry recyclables. The systems resulted in a source separation ratio of 70 wt% for hazardous waste and 76 wt% in the case of WEEE. Results show that households in the study area were willing to increase source separation of hazardous waste and WEEE when accessibility was improved and that this and similar collection systems can play an important role in building up increasingly sustainable solid waste management systems.

  18. Runaway electrons as a source of impurity and reduced fusion yield in the dense plasma focus

    SciTech Connect (OSTI)

    Lerner, Eric J.; Yousefi, Hamid R.

    2014-10-15

    Impurities produced by the vaporization of metals in the electrodes may be a major cause of reduced fusion yields in high-current dense plasma focus devices. We propose here that a major, but hitherto-overlooked, cause of such impurities is vaporization by runaway electrons during the breakdown process at the beginning of the current pulse. This process is sufficient to account for the large amount of erosion observed in many dense plasma focus devices on the anode very near to the insulator. The erosion is expected to become worse with lower pressures, typical of machines with large electrode radii, and would explain the plateauing of fusion yield observed in such machines at higher peak currents. Such runaway electron vaporization can be eliminated by the proper choice of electrode material, by reducing electrode radii and thus increasing fill gas pressure, or by using pre-ionization to eliminate the large fields that create runaway electrons. If these steps are combined with monolithic electrodes to eliminate arcing erosion, large reductions in impurities and large increases in fusion yield may be obtained, as the I{sup 4} scaling is extended to higher currents.

  19. Enhanced field emission from cerium hexaboride coated multiwalled carbon nanotube composite films: A potential material for next generation electron sources

    SciTech Connect (OSTI)

    Patra, Rajkumar; Ghosh, S., E-mail: santanu1@physics.iitd.ac.in [Nanostech Laboratory, Department of Physics, Indian Institute of Technology Delhi, New Delhi-16 (India); Sheremet, E.; Rodriguez, R. D.; Lehmann, D.; Gordan, O. D.; Zahn, D. R. T. [Semiconductor Physics, Technische Universität Chemnitz, 09126 Chemnitz (Germany); Jha, M.; Ganguli, A. K. [Department of Chemistry, Indian Institute of Technology Delhi, New Delhi-16 (India); Schmidt, H. [Material Systems for Nanoelectronics, Technische Universität Chemnitz, 09126 Chemnitz (Germany); Schulze, S. [Solid Surfaces Analysis, Technische Universität Chemnitz, 09126 Chemnitz (Germany); Schmidt, O. G. [Material Systems for Nanoelectronics, Technische Universität Chemnitz, 09126 Chemnitz (Germany); Institute for Integrative Nanosciences, IFW Dresden, Helmholtzstrasse 20, 01069 Dresden (Germany)

    2014-03-07

    Intensified field emission (FE) current from temporally stable cerium hexaboride (CeB{sub 6}) coated carbon nanotubes (CNTs) on Si substrate is reported aiming to propose the new composite material as a potential candidate for future generation electron sources. The film was synthesized by a combination of chemical and physical deposition processes. A remarkable increase in maximum current density, field enhancement factor, and a reduction in turn-on field and threshold field with comparable temporal current stability are observed in CeB{sub 6}-coated CNT film when compared to pristine CeB{sub 6} film. The elemental composition and surface morphology of the films, as examined by scanning electron microscopy, transmission electron microscopy, and energy dispersive X-ray measurements, show decoration of CeB{sub 6} nanoparticles on top and walls of CNTs. Chemical functionalization of CNTs by the incorporation of CeB{sub 6} nanoparticles is evident by a remarkable increase in intensity of the 2D band in Raman spectrum of coated films as compared to pristine CeB{sub 6} films. The enhanced FE properties of the CeB{sub 6} coated CNT films are correlated to the microstructure of the films.

  20. Design and characterization of 2.45 GHz electron cyclotron resonance plasma source with magnetron magnetic field configuration for high flux of hyperthermal neutral beam

    SciTech Connect (OSTI)

    Kim, Seong Bong [Department of Physics, Pohang University of Science and Technology, San 31, Hyoja-dong, Nam-gu, Pohang 790-784 (Korea, Republic of); Convergence Plasma Research Center, National Fusion Research Institute, Gwahangno 113, Yuseong-gu, Daejeon 305-333 (Korea, Republic of); Kim, Dae Chul; Yoo, Suk Jae [Convergence Plasma Research Center, National Fusion Research Institute, Gwahangno 113, Yuseong-gu, Daejeon 305-333 (Korea, Republic of); Namkung, Won; Cho, Moohyun [Department of Physics, Pohang University of Science and Technology, San 31, Hyoja-dong, Nam-gu, Pohang 790-784 (Korea, Republic of)

    2010-08-15

    A 2.45 GHz electron cyclotron resonance (ECR) source with a magnetron magnetic field configuration was developed to meet the demand of a hyperthermal neutral beam (HNB) flux on a substrate of more than 1x10{sup 15} cm{sup -2} s{sup -1} for industrial applications. The parameters of the operating pressure, ion density, electron temperature, and distance between the neutralization plate and the substrate for the HNB source are specified in a theoretical analysis. The electron temperature and the ion density are measured to characterize the ECR HNB source using a Langmuir probe and optical emission spectroscopy. The parameters of the ECR HNB source are in good agreement with the theoretically specified parameters.

  1. Tunable mega-ampere electron current propagation in solids by dynamic control of lattice melt

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    MacLellan, D.? A.; Carroll, D.? C.; Gray, R.? J.; Booth, N.; Burza, M.; Desjarlais, M.? P.; Du, F.; Neely, D.; Powell, H.? W.; Robinson, A.? P.?L.; et al

    2014-10-31

    The influence of lattice-melt-induced resistivity gradients on the transport of mega-ampere currents of fast electrons in solids is investigated numerically and experimentally using laser-accelerated protons to induce isochoric heating. Tailoring the heating profile enables the resistive magnetic fields which strongly influence the current propagation to be manipulated. This tunable laser-driven process enables important fast electron beam properties, including the beam divergence, profile, and symmetry to be actively tailored, and without recourse to complex target manufacture.

  2. Conceptual design of first toroidal electron cyclotron resonance ion source and modeling of ion extraction from it

    E-Print Network [OSTI]

    Caliri, C; Volpe, F A

    2015-01-01

    Electron Cyclotron Resonance Ion Sources (ECRIS) progressed to higher and higher ion currents and charge states by adopting stronger magnetic fields (beneficial for confinement) and proportionally higher ECR frequencies. Further improvements would require the attainment of "triple products" of density, temperature and confinement time comparable with major fusion experiments. For this, we propose a new, toroidal rather than linear, ECRIS geometry, which would at the same time improve confinement and make better use of the magnetic field. Ion extraction is more complicated than from a linear device, but feasible, as our modelling suggests: single-particle tracings showed successful extraction by at least two techniques, making use respectively of a magnetic extractor and of ExB drifts. Additional techniques are briefly discussed.

  3. Ultra-low emittance beam generation using two-color ionization injection in a CO2 laser-driven plasma accelerator

    E-Print Network [OSTI]

    Schroeder, C B; Bulanov, S S; Chen, M; Esarey, E; Geddes, C G R; Vay, J -L; Yu, L -L; Leemans, W P

    2015-01-01

    Ultra-low emittance (tens of nm) beams can be generated in a plasma accelerator using ionization injection of electrons into a wakefield. An all-optical method of beam generation uses two laser pulses of different colors. A long-wavelength drive laser pulse (with a large ponderomotive force and small peak electric field) is used to excite a large wakefield without fully ionizing a gas, and a short-wavelength injection laser pulse (with a small ponderomotive force and large peak electric field), co-propagating and delayed with respect to the pump laser, to ionize a fraction of the remaining bound electrons at a trapped wake phase, generating an electron beam that is accelerated in the wake. The trapping condition, the ionized electron distribution, and the trapped bunch dynamics are discussed. Expressions for the beam transverse emittance, parallel and orthogonal to the ionization laser polarization, are presented. An example is shown using a 10-micron CO2 laser to drive the wake and a frequency-doubled Ti:Al2...

  4. Electron

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submitKansas Nuclear ProfileMultiferroicAward | DepartmentElectron thermal

  5. First time nuclear material detection by one short-pulse-laser...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Technical Articles First time nuclear material detection by one short-pulse-laser-driven neutron source First time nuclear material detection by one short-pulse-laser-driven...

  6. First time nuclear material detection by one short-pulse-laser...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Articles First time nuclear material detection by one short-pulse-laser-driven neutron source First time nuclear material detection by one short-pulse-laser-driven neutron...

  7. Fabrication and characterization of cesium telluride photocathodes: A promising electron source for the Los Alamos Advanced FEL

    SciTech Connect (OSTI)

    Kong, S.H.; Nuguyen, D.C.; Sheffield, R.L.; Sherwood, B.A.

    1994-09-01

    The Advanced FEL at Los Alamos embodies a Y{sub 2}CsSb photocathode as an electron source. The photocathode consists of a K{sub 2}CsSb film deposited on a molybdenum plug that can be inserted into the linac of the FEL. However, because K{sub 2}CsSb is easily contaminated and has a half-life of less than a day when in use, switching to a more rugged high quantum efficiency (QE) material such as Cs{sub 2}Te is considered as a means to lengthen the beam time. Cs{sub 2}Te films were deposited on molybdenum plugs in an ultrahigh-vacuum research chamber. Several Cs{sub 2}Te films were measured in-situ for their spectral responses with a bias voltage of 90V; the resulting QEs were 12-18% at a wavelength of 254 nm, 0.2-1.2% at 334 nm, 10{sup {minus}4}-10{sup {minus}3} at 365 nm, and 10{sup {minus}7}-10{sup {minus}5} at 546 nm. For this cathode to be useful, the authors need to frequency quadruple the 1052 mn line of the Nd:YLF laser to achieve a wavelength of 263 mm. Initial studies showed that the 251-nm QE of Cs{sub 2}Te is much less sensitive to contamination than the 526-nm QE of K{sub 2}CsSb. The authors exposed Cs{sub 2}Te photocathodes to air at 10{sup {minus}4} torr for five minutes. As a result, the QEs dropped from 16-18% to 1-2% at 254 mn. However, heating the cathode to 165{degrees}C revived the QE to about 10%. They conclude that Cs{sub 2}Te is a very rugged photocathode material for use in an rf photoelectron source.

  8. Master-Oscillator-Power-Amplifier (MOPA) Laser Sources Used as Drive Lasers for Photoinjectors for High-Gain, Free Electron Lasers (FELs)

    E-Print Network [OSTI]

    Anlage, Steven

    Master-Oscillator-Power-Amplifier (MOPA) Laser Sources Used as Drive Lasers for Photoinjectors Milchberg #12;- 1 - Abstract The realization of extremely high gain, and high power in Free Electron Lasers critically on the power and phase stability of the cathode drive laser, and conversely the type of FEL output

  9. Ion source

    DOE Patents [OSTI]

    Leung, Ka-Ngo (Hercules, CA); Ehlers, Kenneth W. (Alamo, CA)

    1984-01-01

    A magnetic filter for an ion source reduces the production of undesired ion species and improves the ion beam quality. High-energy ionizing electrons are confined by the magnetic filter to an ion source region, where the high-energy electrons ionize gas molecules. One embodiment of the magnetic filter uses permanent magnets oriented to establish a magnetic field transverse to the direction of travel of ions from the ion source region to the ion extraction region. In another embodiment, low energy 16 eV electrons are injected into the ion source to dissociate gas molecules and undesired ion species into desired ion species.

  10. Optically pulsed electron accelerator

    DOE Patents [OSTI]

    Fraser, J.S.; Sheffield, R.L.

    1985-05-20

    An optically pulsed electron accelerator can be used as an injector for a free electron laser and comprises a pulsed light source, such as a laser, for providing discrete incident light pulses. A photoemissive electron source emits electron bursts having the same duration as the incident light pulses when impinged upon by same. The photoemissive electron source is located on an inside wall of a radiofrequency-powered accelerator cell which accelerates the electron burst emitted by the photoemissive electron source.

  11. Optically pulsed electron accelerator

    DOE Patents [OSTI]

    Fraser, John S. (Los Alamos, NM); Sheffield, Richard L. (Los Alamos, NM)

    1987-01-01

    An optically pulsed electron accelerator can be used as an injector for a free electron laser and comprises a pulsed light source, such as a laser, for providing discrete incident light pulses. A photoemissive electron source emits electron bursts having the same duration as the incident light pulses when impinged upon by same. The photoemissive electron source is located on an inside wall of a radio frequency powered accelerator cell which accelerates the electron burst emitted by the photoemissive electron source.

  12. 2D electron density profile measurement in tokamak by laser-accelerated ion-beam probe

    SciTech Connect (OSTI)

    Chen, Y. H.; Yang, X. Y.; Lin, C. E-mail: cjxiao@pku.edu.cn; Wang, X. G.; Xiao, C. J. E-mail: cjxiao@pku.edu.cn; Wang, L.; Xu, M.

    2014-11-15

    A new concept of Heavy Ion Beam Probe (HIBP) diagnostic has been proposed, of which the key is to replace the electrostatic accelerator of traditional HIBP by a laser-driven ion accelerator. Due to the large energy spread of ions, the laser-accelerated HIBP can measure the two-dimensional (2D) electron density profile of tokamak plasma. In a preliminary simulation, a 2D density profile was reconstructed with a spatial resolution of about 2 cm, and with the error below 15% in the core region. Diagnostics of 2D density fluctuation is also discussed.

  13. Measurement of Electron Density near Plasma Grid of Large-scaled Negative Ion Source by Means of Millimeter-Wave Interferometer

    SciTech Connect (OSTI)

    Nagaoka, K.; Tokuzawa, T.; Tsumori, K.; Nakano, H.; Ito, Y.; Osakabe, M.; Ikeda, K.; Kisaki, M.; Shibuya, M.; Sato, M.; Komada, S.; Kondo, T.; Hayashi, H.; Asano, E.; Takeiri, Y.; Kaneko, O.

    2011-09-26

    A millimeter-wave interferometer with the frequency of 39 GHz ({lambda} 7.7 mm) was newly installed to a large-scaled negative ion source. The measurable line-integrated electron density (n{sub e}l) is from 2x10{sup 16} to 7x10{sup 18} m{sup -2}, where n{sub e} and l represent an electron density and the plasma length along the millimeter-wave path, respectively. Our interest in this study is behavior of negative ions and reduction of electron density in the beam extraction region near the plasma grid. The first results show the possibility of the electron density measurement by the millimeter-wave interferometer in this region. The line-averaged electron density increases proportional to the arc power under the condition without cesium seeding. The significant decrease of the electron density and significant increase of the negative ion density were observed just after the cesium seeding. The electron density measured with the interferometer agrees well with that observed with a Langmuir probe. The very high negative ion ratio of n{sub H-}/(n{sub e}+n{sub H-}) = 0.85 was achieved within 400 min. after the cesium seeding.

  14. Influence of the contact potential and space-charge effect on the performance of a Stoffel-Johnson design electron source for inverse photoemission spectroscopy

    SciTech Connect (OSTI)

    Maniraj, M.; Barman, Sudipta Roy [UGC-DAE Consortium for Scientific Research, Khandwa Road, Indore 452001, Madhya Pradesh (India)] [UGC-DAE Consortium for Scientific Research, Khandwa Road, Indore 452001, Madhya Pradesh (India)

    2014-03-15

    By imaging the spatial intensity distribution of the electrons from a Stoffel-Johnson (SJ) type low energy electron source for inverse photoemission spectroscopy (IPES), we find that the focus is distorted when the beam current exceeds the limiting value due to space charge effect. The space charge effect and the contact potential difference suppress the beam current at low energies (<10 eV). In this work, we show that these limitations of the SJ source can be overcome by compensation of the contact potential difference between the cathode and the lens electrodes and an uniform well focused electron beam with the set kinetic energy can be obtained. The size of the electron beam is around 1 mm full width at half maximum over the whole energy range of 5 to 30 eV generally used for IPES. The compensation of the contact potential difference also enhances the beam current substantially at low energies (<10 eV) and uniform beam current is achieved for the whole energy range. We find that the drift in the electron beam position is sensitive to the lens electrode separation and it is about 1 mm over the whole energy range. By measuring the n = 1 image potential state on Cu(100), we show that the resolution is better when the cathode filament current is set to lower values.

  15. Estimates of the absorbed fraction of energy for various electron source and target regions in the upper respiratory tract 

    E-Print Network [OSTI]

    Calvo, Sebastian

    1994-01-01

    . ACKNOWLEDGMENTS The author would like to thank committee members Drs. Wesley Bolch and John Poston of thc Nuclear Engineering Department, Dr. Keith Eckerman of the Oak Ridge National Laboratory and the Nuclear Engineering Department, and Dr. Michael Walker... INFORMATION MATERIALS AND METHODS . The Model Used in This Study EGS4 Code RESULTS . Source in Tracheal Airway Source on Tracheal Airway Surface Source on Carinal Ridge Surface Source in Airways of Main Bronchi and Bifurcation Zone DISCUSSION...

  16. Laser Plasma Particle Accelerators: Large Fields for Smaller Facility Sources

    E-Print Network [OSTI]

    Geddes, Cameron G.R.

    2010-01-01

    of high- gradient, laser plasma particle accelerators.accelerators that use laser-driven plasma waves. Theseleft) showing the laser (red), plasma wake density (purple-

  17. Hydrogen negative ion production in a 14 GHz electron cyclotron resonance compact ion source with a cone-shaped magnetic filter

    SciTech Connect (OSTI)

    Ichikawa, T.; Kasuya, T.; Wada, M., E-mail: mwada@mail.doshisha.ac.jp [Graduate School of Engineering, Doshisha University, Kyotanabe, Kyoto (Japan); Kenmotsu, T. [School of Biomedical Sciences, Doshisha University, Kyotanabe, Kyoto (Japan)] [School of Biomedical Sciences, Doshisha University, Kyotanabe, Kyoto (Japan); Maeno, S. [Novelion Systems Co. Ltd., Kyotanabe, Kyoto (Japan)] [Novelion Systems Co. Ltd., Kyotanabe, Kyoto (Japan); Nishiura, M.; Shimozuma, T. [National Institute for Fusion Science, Toki, Gifu (Japan)] [National Institute for Fusion Science, Toki, Gifu (Japan); Yamaoka, H. [RIKEN SPring-8 Center, Sayo, Hyogo (Japan)] [RIKEN SPring-8 Center, Sayo, Hyogo (Japan)

    2014-02-15

    The plasma electrode structure of a 14 GHz ECR ion source was modified to enlarge the plasma volume of low electron temperature region. The result shows that the extracted beam current reached about 0.6 mA/cm{sup 2} with about 40 W microwave power. To investigate the correlation between the volume of the low electron temperature region and the H{sup ?} current, a vacuum ultraviolet (VUV) spectrometer had been installed to observe light emission in the VUV wavelength range from the plasma. From the results of the negative ion beam current and that from VUV spectrometry, production rate of vibrationally excited hydrogen molecule seems to be enhanced by increasing the volume of low electron temperature region.

  18. X-ray laser driven gold targets

    SciTech Connect (OSTI)

    Petrova, Tz. B., E-mail: lina.petrova@nrl.navy.mil; Whitney, K. G.; Davis, J. [Plasma Physics Division, Naval Research Laboratory, 4555 Overlook Ave. SW, Washington, DC 20375 (United States)] [Plasma Physics Division, Naval Research Laboratory, 4555 Overlook Ave. SW, Washington, DC 20375 (United States)

    2014-03-15

    The femtosecond population dynamics of gold irradiated by a coherent high-intensity (>10{sup 17}?W/cm{sup 2}) x-ray laser pulse is investigated theoretically. There are two aspects to the assembled model. One is the construction of a detailed model of platinum-like gold inclusive of all inner-shell states that are created by photoionization of atomic gold and decay either by radiative or Auger processes. Second is the computation of the population dynamics that ensues when an x-ray pulse is absorbed in gold. The hole state generation depends on the intensity and wavelength of the driving x-ray pulse. The excited state populations reached during a few femtosecond timescales are high enough to generate population inversions, whose gain coefficients are calculated. These amplified lines in the emitted x-ray spectrum provide important diagnostics of the radiation dynamics and also suggest a nonlinear way to increase the frequency of the coherent output x-ray pulses relative to the frequency of the driver input x-ray pulse.

  19. Laser Driven Dynamic Loading of Condensed Matter

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformationJesse Bergkamp Graduate studentScienceLaboratoryandBryan CurriculumGeoffreyLaser

  20. Experimental demonstration of longitudinal beam phase space linearizer in a free-electron laser facility by corrugated structures

    E-Print Network [OSTI]

    Deng, Haixiao; Feng, Chao; Zhang, Tong; Wang, Xingtao; Lan, Taihe; Feng, Lie; Zhang, Wenyan; Liu, Xiaoqing; Yao, Haifeng; Shen, Lei; Li, Bin; Zhang, Junqiang; Li, Xuan; Fang, Wencheng; Wang, Dan; Couprie, Marie-emmanuelle; Lin, Guoqiang; Liu, Bo; Gu, Qiang; Wang, Dong; Zhao, Zhentang

    2014-01-01

    Removal of residual linear energy chirp and intrinsic nonlinear energy curvature in the relativistic electron beam from radiofrequency linear accelerator is of paramount importance for efficient lasing of a high-gain free-electron laser. Recently, it was theoretically and experimentally demonstrated that the longitudinal wakefield excited by the electrons itself in the corrugated structure allows for precise control of the electron beam phase space. In this Letter, we report the first utilization of a corrugated structure as beam linearizer in the operation of a seeded free-electron laser driven by a 140 MeV linear accelerator, where a gain of ~10,000 over spontaneous emission was achieved at the second harmonic of the 1047 nm seed laser, and a free-electron laser bandwidth narrowing by about 50% was observed, in good agreement with the theoretical expectations.

  1. High-power magnetron transmitter as an RF source for the electron collider ring of the MEIC facility

    E-Print Network [OSTI]

    Kazakevich, G

    2014-01-01

    A novel concept of high-power transmitters utilizing the Continuous Wave (CW) magnetrons, frequency-locked by phase-modulated signals has been proposed to compensate energy losses caused by Synchrotron Radiation (SR) in the electron ring of the MEIC facility. At operating frequency of about 750 MHz the SR losses are ~2 MW. They can be compensated by some number of Superconducting RF (SRF) cavities at the feeding power of about 100-200 kW per cavity. A high-power CW transmitters, based on magnetrons, frequency-locked by phase-modulated signal, allowing a wide-band control in phase and power, and associated with a wide-band closed feedback loop are proposed to feed the SRF cavities to compensate the SR losses of the electron beam in the MEIC collider electron ring.

  2. Beam dynamics study of a 30?MeV electron linear accelerator to drive a neutron source

    SciTech Connect (OSTI)

    Kumar, Sandeep; Yang, Haeryong; Kang, Heung-Sik

    2014-02-14

    An experimental neutron facility based on 32?MeV/18.47?kW electron linac has been studied by means of PARMELA simulation code. Beam dynamics study for a traveling wave constant gradient electron accelerator is carried out to reach the preferential operation parameters (E?=?30?MeV, P?=?18?kW, dE/E?electron energy is required to produce acceptable neutron flux. The final neutron flux is estimated to be 5?×?10{sup 11}?n/cm{sup 2}/s/mA. Future development will be the real design of a 30?MeV electron linac based on S band traveling wave.

  3. Pulsar Wind Nebulae as a source of the observed electron and positron excess at high energy: the case of Vela-X

    E-Print Network [OSTI]

    Della Torre, S; Rancoita, P G; Rozza, D; Treves, A

    2015-01-01

    We investigate, in terms of production from pulsars and their nebulae, the cosmic ray positron and electron fluxes above $\\sim10$ GeV, observed by the AMS-02 experiment up to 1 TeV. We concentrate on the Vela-X case. Starting from the gamma-ray photon spectrum of the source, generated via synchrotron and inverse Compton processes, we estimated the electron and positron injection spectra. Several features are fixed from observations of Vela-X and unknown parameters are borrowed from the Crab nebula. The particle spectra produced in the pulsar wind nebula are then propagated up to the Solar System, using a diffusion model. Differently from previous works, the omnidirectional intensity excess for electrons and positrons is obtained as a difference between the AMS-02 data and the corresponding local interstellar spectrum. An equal amount of electron and positron excess is observed and we interpreted this excess (above $\\sim$100 GeV in the AMS-02 data) as a supply coming from Vela-X. The particle contribution is c...

  4. Note: Effect of hot liner in producing {sup 40,48}Ca beam from RIKEN 18-GHz electron cyclotron resonance ion source

    SciTech Connect (OSTI)

    Ozeki, K. Higurashi, Y.; Kidera, M.; Nakagawa, T.

    2015-01-15

    In order to produce a high-intensity and stable {sup 48}Ca beam from the RIKEN 18-GHz electron cyclotron resonance ion source, we have begun testing the production of a calcium beam using a micro-oven. To minimize the consumption rate of the material ({sup 48}Ca), we introduced the “hot liner” method and investigated the effect of the liner on the material consumption rate. The micro-oven was first used to produce the {sup 48}Ca beam for experiments in the RIKEN radioisotope beam factory, and a stable beam could be supplied for a long time with low consumption rate.

  5. Ion sources with arc-discharge plasma box driven by directly heated LaB{sub 6} electron emitter or cold cathode (invited)

    SciTech Connect (OSTI)

    Ivanov, Alexander A.; Davydenko, Vladimir I.; Deichuli, Petr P.; Shulzhenko, Grigori I.; Stupishin, Nikolay V.

    2008-02-15

    In the Budker Institute, Novosibirsk, an ion source with arc-discharge plasma box has been developed in the recent years for application in thermonuclear devices for plasma diagnostics. Several modifications of the ion source were provided with extracted current ranging from 1 to 7 A and pulse duration of up to 4 s. Initially, the arc-discharge plasma box with cold cathode was used, with which pulse duration is limited to 2 s by the cathode overheating and sputtering in local arc spots. Recently, a directly heated LaB{sub 6} electron emitter was employed instead, which has extended lifetime compared to the cold cathode. In the paper, characteristics of the beam produced with both arrangements of the plasma box are presented.

  6. X-ray-optical cross-correlator for gas-phase experiments at the Linac Coherent Light Source free-electron laser

    SciTech Connect (OSTI)

    Schorb, S.; Cryan, J. P.; Glownia, J. M.; Bionta, M. R.; Coffee, R. N.; Swiggers, M.; Carron, S.; Castagna, J.-C.; Bozek, J. D.; Messerschmidt, M.; Schlotter, W. F.; Bostedt, C. [Linac Coherent Light Source, SLAC National Accelerator Laboratory, P.O. Box 20450, Stanford, California 94309 (United States); Gorkhover, T. [Institut fuer Optik und Atomare Physik, Technische Universitaet Berlin, Hardenbergstr. 36, 10623 Berlin (Germany); Erk, B.; Boll, R.; Schmidt, C.; Rudenko, A. [Max-Planck Advanced-Study-Group at CFEL, Notkestr. 85, 22607 Hamburg (Germany); Max-Planck-Institut f. Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany); Rolles, D. [Max-Planck Advanced-Study-Group at CFEL, Notkestr. 85, 22607 Hamburg (Germany); Max-Planck-Institut f. med. Forschung, Jahnstr. 29, 69120 Heidelberg (Germany); Rouzee, A. [Max-Born-Institut, Max-Born-Str. 2, 12489 Berlin (Germany)

    2012-03-19

    X-ray-optical pump-probe experiments at the Linac Coherent Light Source (LCLS) have so far been limited to a time resolution of 280 fs fwhm due to timing jitter between the accelerator-based free-electron laser (FEL) and optical lasers. We have implemented a single-shot cross-correlator for femtosecond x-ray and infrared pulses. A reference experiment relying only on the pulse arrival time information from the cross-correlator shows a time resolution better than 50 fs fwhm (22 fs rms) and also yields a direct measurement of the maximal x-ray pulse length. The improved time resolution enables ultrafast pump-probe experiments with x-ray pulses from LCLS and other FEL sources.

  7. Waveguide slot-excited long racetrack electron cyclotron resonance plasma source for roll-to-roll (scanning) processing

    SciTech Connect (OSTI)

    You, H.-J. [National Fusion Research Institute, Daejeon (Korea, Republic of)] [National Fusion Research Institute, Daejeon (Korea, Republic of)

    2013-07-15

    We present a SLot-excited ANtenna (SLAN) long racetrack ECR plasma source that is utilized for roll-to-roll plasma processing such as thin film encapsulation of large-area OLED (organic light emitting diode) panel or modification of fabric surfaces. This source is designed to be long, and to operate under high density uniform plasma with sub-milli-torr pressures. The above features are accomplished by a slot-excited long racetrack resonator with a toroidal geometry of magnetic field ECR configuration, and reinforced microwave electric distributions along the central region of plasma chamber. Also, a new feature has been added to the source. This is to employ a tail plunger, which allows the microwave electric field and the uniformity of the plasma profile to be easily adjustable. We have successfully generated Ar plasmas operating with the microwave power of 0.5–3 kW in the pressure range of 0.2–10 mTorr. The plasma is uniform (<10%) in the direction of the straight track and has a Gaussian profile in the roll-to-roll (scanning) direction. In addition, it is shown that the tail plunger could adjust the plasma profile in order to obtain plasma uniformity. Furthermore, based on the results, we suggest a newly designed up-scaled racetrack-SLAN source.

  8. Future Synchrotron Light Sources Based on Ultimate Storage Rings...

    Office of Scientific and Technical Information (OSTI)

    ACCELERATORS; APERTURES; BRIGHTNESS; DIFFRACTION; ELECTRON BEAMS; ELECTRONS; ENERGY RECOVERY; LIFETIME; LIGHT SOURCES; LINEAR ACCELERATORS; OPTIMIZATION; PHOTONS;...

  9. 500 MW X-Band RF System of a 0.25 GeV Electron LINAC for Advanced Compton Scattering Source Application

    SciTech Connect (OSTI)

    Chu, Tak Sum; /LLNL, Livermore; Anderson, Scott; /LLNL, Livermore; Barty, Christopher; /LLNL, Livermore; Gibson, David; /LLNL, Livermore; Hartemann, Fred; /LLNL, Livermore; Marsh, Roark; /LLNL, Livermore; Siders, Craig; /LLNL, Livermore; Adolphsen, Chris; /SLAC; Jongewaard, Erik; /SLAC; Raubenheimer, Tor; /SLAC; Tantawi, Sami; /SLAC; Vlieks, Arnold; /SLAC; Wang, Juwen; /SLAC

    2012-07-03

    A Mono-Energetic Gamma-Ray (MEGa-Ray) Compton scattering light source is being developed at LLNL in collaboration with the SLAC National Accelerator Laboratory. The electron beam for the Compton scattering interaction will be generated by a X-band RF gun and a X-band LINAC at the frequency of 11.424 GHz. High power RF in excess of 500 MW is needed to accelerate the electrons to energy of 250 MeV or greater for the interaction. Two high power klystron amplifiers, each capable of generating 50 MW, 1.5 msec pulses, will be the main high power RF sources for the system. These klystrons will be powered by state of the art solid-state high voltage modulators. A RF pulse compressor, similar to the SLED II pulse compressor, will compress the klystron output pulse with a power gain factor of five. For compactness consideration, we are looking at a folded waveguide setup. This will give us 500 MW at output of the compressor. The compressed pulse will then be distributed to the RF gun and to six traveling wave accelerator sections. Phase and amplitude control are located at the RF gun input and additional control points along the LINAC to allow for parameter control during operation. This high power RF system is being designed and constructed. In this paper, we will present the design, layout, and status of this RF system.

  10. 500 MW X-BAND RF SYSTEM OF A 0.25 GEV ELECTRON LINAC FOR ADVANCED COMPTON SCATTERING SOURCE APPLICATION

    SciTech Connect (OSTI)

    Chu, T S; Anderson, S G; Gibson, D J; Hartemann, F V; Marsh, R A; Siders, C; Barty, C P; Adolphsen, C; Jongewaard, E; Tantawi, S; Vlieks, A; Wang, J W; Raubenheimer, T

    2010-05-12

    A Mono-Energetic Gamma-Ray (MEGa-Ray) Compton scattering light source is being developed at LLNL in collaboration with SLAC National Accelerator Laboratory. The electron beam for the Compton scattering interaction will be generated by a X-band RF gun and a X-band LINAC at the frequency of 11.424 GHz. High power RF in excess of 500 MW is needed to accelerate the electrons to energy of 250 MeV or greater for the interaction. Two high power klystron amplifiers, each capable of generating 50 MW, 1.5 msec pulses, will be the main high power RF sources for the system. These klystrons will be powered by state of the art solid-state high voltage modulators. A RF pulse compressor, similar to the SLED II pulse compressor, will compress the klystron output pulse with a power gain factor of five. For compactness consideration, we are looking at a folded waveguide setup. This will give us 500 MW at output of the compressor. The compressed pulse will then be distributed to the RF gun and to six traveling wave accelerator sections. Phase and amplitude control are located at the RF gun input and additional control points along the LINAC to allow for parameter control during operation. This high power RF system is being designed and constructed. In this paper, we will present the design, layout, and status of this RF system.

  11. Optical gating and streaking of free-electrons with attosecond precision

    E-Print Network [OSTI]

    Kozak, Martin; Leedle, Kenneth J; Schoenenberger, Norbert; Ruehl, Alex; Hartl, Ingmar; Harris, James S; Byer, Robert L; Hommelhoff, Peter

    2015-01-01

    In this paper we present proof of principle experiments of an optical gating concept for free electrons. We demonstrate a temporal resolution of 1.2+-0.3 fs via energy and transverse momentum modulation as a function of time. The scheme is based on the synchronous interaction between electrons and the near-field mode of a dielectric nano-grating excited by a femtosecond laser pulse with an optical period duration of 6.5 fs. The sub-optical cycle resolution demonstrated here is promising for use in laser-driven streak cameras for attosecond temporal characterization of bunched particle beams as well as time-resolved experiments with free-electron beams. We expect that 10 as temporal resolution will be achieved in the near future using such a scheme.

  12. Comparison of TG-43 and TG-186 in breast irradiation using a low energy electronic brachytherapy source

    SciTech Connect (OSTI)

    White, Shane A.; Landry, Guillaume; Reniers, Brigitte; Fonseca, Gabriel Paiva; Beaulieu, Luc; Verhaegen, Frank

    2014-06-15

    Purpose: The recently updated guidelines for dosimetry in brachytherapy in TG-186 have recommended the use of model-based dosimetry calculations as a replacement for TG-43. TG-186 highlights shortcomings in the water-based approach in TG-43, particularly for low energy brachytherapy sources. The Xoft Axxent is a low energy (<50 kV) brachytherapy system used in accelerated partial breast irradiation (APBI). Breast tissue is a heterogeneous tissue in terms of density and composition. Dosimetric calculations of seven APBI patients treated with Axxent were made using a model-based Monte Carlo platform for a number of tissue models and dose reporting methods and compared to TG-43 based plans. Methods: A model of the Axxent source, the S700, was created and validated against experimental data. CT scans of the patients were used to create realistic multi-tissue/heterogeneous models with breast tissue segmented using a published technique. Alternative water models were used to isolate the influence of tissue heterogeneity and backscatter on the dose distribution. Dose calculations were performed using Geant4 according to the original treatment parameters. The effect of the Axxent balloon applicator used in APBI which could not be modeled in the CT-based model, was modeled using a novel technique that utilizes CAD-based geometries. These techniques were validated experimentally. Results were calculated using two dose reporting methods, dose to water (D{sub w,m}) and dose to medium (D{sub m,m}), for the heterogeneous simulations. All results were compared against TG-43-based dose distributions and evaluated using dose ratio maps and DVH metrics. Changes in skin and PTV dose were highlighted. Results: All simulated heterogeneous models showed a reduced dose to the DVH metrics that is dependent on the method of dose reporting and patient geometry. Based on a prescription dose of 34 Gy, the average D{sub 90} to PTV was reduced by between ?4% and ?40%, depending on the scoring method, compared to the TG-43 result. Peak skin dose is also reduced by 10%–15% due to the absence of backscatter not accounted for in TG-43. The balloon applicator also contributed to the reduced dose. Other ROIs showed a difference depending on the method of dose reporting. Conclusions: TG-186-based calculations produce results that are different from TG-43 for the Axxent source. The differences depend strongly on the method of dose reporting. This study highlights the importance of backscatter to peak skin dose. Tissue heterogeneities, applicator, and patient geometries demonstrate the need for a more robust dose calculation method for low energy brachytherapy sources.

  13. Radiation source

    DOE Patents [OSTI]

    Thode, Lester E. (Los Alamos, NM)

    1981-01-01

    A device and method for relativistic electron beam heating of a high-density plasma in a small localized region. A relativistic electron beam generator or accelerator produces a high-voltage electron beam which propagates along a vacuum drift tube and is modulated to initiate electron bunching within the beam. The beam is then directed through a low-density gas chamber which provides isolation between the vacuum modulator and the relativistic electron beam target. The relativistic beam is then applied to a high-density target plasma which typically comprises DT, DD, or similar thermonuclear gas at a density of 10.sup.17 to 10.sup.20 electrons per cubic centimeter. The target gas is ionized prior to application of the relativistic electron beam by means of a laser or other preionization source to form a plasma. Utilizing a relativistic electron beam with an individual particle energy exceeding 3 MeV, classical scattering by relativistic electrons passing through isolation foils is negligible. As a result, relativistic streaming instabilities are initiated within the high-density target plasma causing the relativistic electron beam to efficiently deposit its energy into a small localized region of the high-density plasma target.

  14. A liquid-helium-free superconducting coil system forming a flat minimum-magnetic-field distribution of an electron cyclotron resonance ion source

    SciTech Connect (OSTI)

    Yoshida, Ken-ichi, E-mail: yoshida.kennichi71@jaea.go.jp; Nara, Takayuki; Saitoh, Yuichi; Yokota, Watalu [Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency, 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan)] [Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency, 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan)

    2014-02-15

    A flat distribution of the minimum magnetic field (flat-B{sub min}) of an electron cyclotron resonance ion source (ECRIS) is expected to perform better in highly charged ion production than classical B{sub min}. To form a flat-B{sub min} structure with a liquid helium-free superconducting device, a coil system of seven coils with four current leads has been designed. The lead number was reduced by connecting the plural coils in series to maintain the flat-B{sub min} structure even when the coil currents are changed for adjustment. This coil system can be operated with a helium-free cryostat, since the estimation of heat from the leads to the coils is nearly equivalent to the existing superconducting ECRIS of a similar type.

  15. Doping and electronic properties of GaAs grown by close-spaced vapor transport from powder sources for scalable III–V photovoltaics

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ritenour, Andrew J.; Boucher, Jason W.; DeLancey, Robert; Greenaway, Ann L.; Aloni, Shaul; Boettcher, Shannon W.

    2014-09-01

    We report the use of a simple close-spaced vapor transport technique for the growth of high-quality epitaxial GaAs films using potentially inexpensive GaAs powders as precursors. The free carrier type and density (1016 to 1019 cm–3) of the films were adjusted by addition of Te or Zn powder to the GaAs source powder. We show using photoelectrochemical and electron beam-induced current analyses that the minority carrier diffusion lengths of the n- and p-GaAs films reached ~3 ?m and ~8 ?m, respectively. Hall mobilities approach those achieved for GaAs grown by metal–organic chemical vapor deposition, 1000–4200 cm2 V–1 s–1 for n-GaAsmore »and 50–240 cm V–1 s–1 for p-GaAs depending on doping level. We conclude that the electronic quality of GaAs grown by close-spaced vapor transport is similar to that of GaAs made using conventional techniques and is thus sufficient for high-performance photovoltaic applications.« less

  16. Doping and electronic properties of GaAs grown by close-spaced vapor transport from powder sources for scalable III–V photovoltaics

    SciTech Connect (OSTI)

    Ritenour, Andrew J.; Boucher, Jason W.; DeLancey, Robert; Greenaway, Ann L.; Aloni, Shaul; Boettcher, Shannon W.

    2014-09-01

    We report the use of a simple close-spaced vapor transport technique for the growth of high-quality epitaxial GaAs films using potentially inexpensive GaAs powders as precursors. The free carrier type and density (1016 to 1019 cm–3) of the films were adjusted by addition of Te or Zn powder to the GaAs source powder. We show using photoelectrochemical and electron beam-induced current analyses that the minority carrier diffusion lengths of the n- and p-GaAs films reached ~3 ?m and ~8 ?m, respectively. Hall mobilities approach those achieved for GaAs grown by metal–organic chemical vapor deposition, 1000–4200 cm2 V–1 s–1 for n-GaAs and 50–240 cm V–1 s–1 for p-GaAs depending on doping level. We conclude that the electronic quality of GaAs grown by close-spaced vapor transport is similar to that of GaAs made using conventional techniques and is thus sufficient for high-performance photovoltaic applications.

  17. Final report for the NSF/DOE partnership in basic plasma science grant DE-FG02-06ER54906 '?Laser-driven collisionless shocks in the Large Plasma Device'?

    SciTech Connect (OSTI)

    Niemann, Christoph; Gekelman, W.; Winske, D.; Larsen, D.

    2012-12-14

    We have performed several thousand high-energy laser shots in the LAPD to investigate the dynamics of an exploding laser-produced plasma in a large ambient magneto-plasma. Debris-ions expanding at super-Alfvenic velocity (up to MA=1.5) expel the ambient magnetic field, creating a large (> 20 cm) diamagnetic cavity. We observed field compressions of up to B/B{sub 0} = 1.5 at the edge of the bubble, consistent with the MHD jump conditions, as well as localized electron heating at the edge of the bubble. Two-dimensional hybrid simulations reproduce these measurements well and show that the majority of the ambient ions are energized by the magnetic piston to super-Alfvenic speeds and swept outside the bubble volume. Nonlinear shear-Alfven waves ({delta}B/B{sub 0} > 25%) are radiated from the cavity with a coupling efficiency of 70% from magnetic energy in the bubble to the wave. While the data is consistent with a weak magneto-sonic shock, the experiments were severely limited by the low ambient plasma densities (10{sup 12} cm{sup -3}). 2D hybrid simulations indicate that future experiments with the new LAPD plasma source and densities in excess of 10{sup 13} cm{sup -3} will drive full-blown collisionless shocks with MA>10 over several c/wpi and shocked Larmor radii. In a separate experiment at the LANL Trident laser facility we have performed a proof-of-principle experiment at higher densities to demonstrate key elements of collisionless shocks in laser-produced magnetized plasmas with important implications to NIF. Simultaneously we have upgraded the UCLA glass-laser system by adding two large amplitude disk amplifiers from the NOVA laser and boost the on-target energy from 30 J to up to 1 kJ, making this one of the world’s largest university-scale laser systems. We now have the infrastructure in place to perform novel and unique high-impact experiments on collision-less shocks at the LAPD.

  18. Frontiers in Chemical Imaging Seminar Series

    E-Print Network [OSTI]

    ... Howard Padmore Division Deputy for Experimental Systems Advanced Light Source Abstract Free Electron to the quality of the electron beam; typically this beam is produced by a laser-driven photocathode, before acceleration to relativistic velocity in a linear accelerator. A lower emittance beam can be used to lase

  19. NEWS & VIEWS 92 nature physics | VOL 4 | FEBRUARY 2008 | www.nature.com/naturephysics

    E-Print Network [OSTI]

    Loss, Daniel

    emitted Synchrotron radiation generated using an electron beam from a laser-driven accelerator opens-RAY SOURCES Towards a table-top free-electron laser Kazuhisa Nakajima is at the High Energy Accelerator, enabling the dynamics of chemical reactions, materials and biomolecular systems to be studied

  20. Optimizing C{sup 4+} and C{sup 5+} beams of the Kei2 electron cyclotron resonance ion source using a special gas-mixing technique

    SciTech Connect (OSTI)

    Drentje, A.G.; Muramatsu, M.; Kitagawa, A.

    2006-03-15

    With the prototype electron cyclotron resonance ion source for the next carbon therapy facility in Japan a series of measurements has been performed in order (a) to find the best condition for producing high beam currents of C{sup 4+} ions, and (b) to study the effect of 'special' gas mixing by using a chemical compound as a feed gas. The effect would then appear as an increase in high charge state production in this case of C{sup 5+} ions. In 'regular' gas-mixing experiments it is well known that an isotopic phenomenon occurs: a heavier isotope of the mixing gas is increasing the production of high charge states of the beam gas ions. A similar isotopic effect has been found in the present experiment: with deuterated methane (CD{sub 4} gas) the C{sup 5+} beam currents are about 10% higher than with regular methane (CH{sub 4} gas). The 'mixing-gas' ratio D (or H) to C can be decreased by choosing, e.g., butane gas; in this case the isotopic effect for C{sup 5+} production is even stronger (>15%). For production of C{sup 4+} ions the isotopic effect appears to be absent. Clearly this is related to the much easier production. It turns out that the relative amount of carbon is much more important: butane gives about 10% higher C{sup 4+}-ion currents than methane.

  1. Simultaneous usage of pinhole and penumbral apertures for imaging small scale neutron sources from inertial confinement fusion experiments

    SciTech Connect (OSTI)

    Guler, N.; Volegov, P.; Danly, C. R.; Grim, G. P.; Merrill, F. E.; Wilde, C. H. [Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, New Mexico 87545 (United States)

    2012-10-15

    Inertial confinement fusion experiments at the National Ignition Facility are designed to understand the basic principles of creating self-sustaining fusion reactions by laser driven compression of deuterium-tritium (DT) filled cryogenic plastic capsules. The neutron imaging diagnostic provides information on the distribution of the central fusion reaction region and the surrounding DT fuel by observing neutron images in two different energy bands for primary (13-17 MeV) and down-scattered (6-12 MeV) neutrons. From this, the final shape and size of the compressed capsule can be estimated and the symmetry of the compression can be inferred. These experiments provide small sources with high yield neutron flux. An aperture design that includes an array of pinholes and penumbral apertures has provided the opportunity to image the same source with two different techniques. This allows for an evaluation of these different aperture designs and reconstruction algorithms.

  2. 1

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Laser-driven neutron source for research and global security August 16, 2015 View larger version Laser-driven neutron source for research and global security At Los Alamos's...

  3. VOLUME 82, NUMBER 26 P H Y S I C A L R E V I E W L E T T E R S 28 JUNE 1999 Laser-Driven Atomic Pump

    E-Print Network [OSTI]

    Tománek, David

    by the direct force Fd due to the external field that is locally modified at the atomic site, and by the wind driving could be realized if the atoms would take better advantage of the large unidirectional momenta and energy carried by the hot electrons. This type of driving can be realized in photovoltaic materials

  4. Multi-MeV electron acceleration by sub-terawatt laser pulses

    E-Print Network [OSTI]

    Goers, A J; Feder, L; Miao, B; Salehi, F; Milchberg, H M

    2015-01-01

    We demonstrate laser-plasma acceleration of high charge electron beams to the ~10 MeV scale using ultrashort laser pulses with as little energy as 10 mJ. This result is made possible by an extremely dense and thin hydrogen gas jet. Total charge up to ~0.5 nC is measured for energies >1 MeV. Acceleration is correlated to the presence of a relativistically self-focused laser filament accompanied by an intense coherent broadband light flash, associated with wavebreaking, which can radiate more than ~3% of the laser energy in a sub-femtosecond bandwidth consistent with half-cycle optical emission. Our results enable truly portable applications of laser-driven acceleration, such as low dose radiography, ultrafast probing of matter, and isotope production.

  5. Improved ion source

    DOE Patents [OSTI]

    Leung, K.N.; Ehlers, K.W.

    1982-05-04

    A magnetic filter for an ion source reduces the production of undesired ion species and improves the ion beam quality. High-energy ionizing electrons are confined by the magnetic filter to an ion source region, where the high-energy electrons ionize gas molecules. One embodiment of the magnetic filter uses permanent magnets oriented to establish a magnetic field transverse to the direction of travel of ions from the ion source region to the ion extraction region. In another embodiment, low energy 16 eV electrons are injected into the ion source to dissociate gas molecules and undesired ion species into desired ion species,

  6. The components for a quantum computer based on surface state electrons on liquid helium

    E-Print Network [OSTI]

    Naberhuis, Brian Patrick

    2007-01-01

    Silicon Diode as a Source of Low-Energy Free Electrons atdiode as a source of low energy (free electrons

  7. The direct injection of intense ion beams from a high field electron cyclotron resonance ion source into a radio frequency quadrupole

    SciTech Connect (OSTI)

    Rodrigues, G. Kanjilal, D.; Roy, A.; Becker, R.; Baskaran, R.

    2014-02-15

    The ion current achievable from high intensity ECR sources for highly charged ions is limited by the high space charge. This makes classical extraction systems for the transport and subsequent matching to a radio frequency quadrupole (RFQ) accelerator less efficient. The direct plasma injection (DPI) method developed originally for the laser ion source avoids these problems and uses the combined focusing of the gap between the ion source and the RFQ vanes (or rods) and the focusing of the rf fields from the RFQ penetrating into this gap. For high performance ECR sources that use superconducting solenoids, the stray magnetic field of the source in addition to the DPI scheme provides focusing against the space charge blow-up of the beam. A combined extraction/matching system has been designed for a high performance ECR ion source injecting into an RFQ, allowing a total beam current of 10 mA from the ion source for the production of highly charged {sup 238}U{sup 40+} (1.33 mA) to be injected at an ion source voltage of 60 kV. In this design, the features of IGUN have been used to take into account the rf-focusing of an RFQ channel (without modulation), the electrostatic field between ion source extraction and the RFQ vanes, the magnetic stray field of the ECR superconducting solenoid, and the defocusing space charge of an ion beam. The stray magnetic field is shown to be critical in the case of a matched beam.

  8. Electronic Monitoring White Papers

    E-Print Network [OSTI]

    Electronic Monitoring White Papers February 15, 2013 Source: NOAA Fisheries Office of Policy & Electronic Monitoring Working Group U.S. Department of Commerce National Oceanic & Atmospheric Administration.holliday@noaa.gov #12;B-1 Appendix B - Electronic Monitoring White Paper Existing Technologies National Oceanic

  9. Selective ion source

    DOE Patents [OSTI]

    Leung, Ka-Ngo (Hercules, CA)

    1996-01-01

    A ion source is described wherein selected ions maybe extracted to the exclusion of unwanted ion species of higher ionization potential. Also described is a method of producing selected ions from a compound, such as P.sup.+ from PH.sub.3. The invention comprises a plasma chamber, an electron source, a means for introducing a gas to be ionized by electrons from the electron source, means for limiting electron energy from the electron source to a value between the ionization energy of the selected ion species and the greater ionization energy of an unwanted ion specie, and means for extracting the target ion specie from the plasma chamber. In one embodiment, the electrons are generated in a plasma cathode chamber immediately adjacent to the plasma chamber. A small extractor draws the electrons from the plasma cathode chamber into the relatively positive plasma chamber. The energy of the electrons extracted in this manner is easily controlled. The invention is particularly useful for doping silicon with P.sup.+, AS.sup.+, and B.sup.+ without the problematic presence of hydrogen, helium, water, or carbon oxide ions. Doped silicon is important for manufacture of semiconductors and semiconductor devices.

  10. Selective ion source

    DOE Patents [OSTI]

    Leung, K.N.

    1996-05-14

    A ion source is described wherein selected ions maybe extracted to the exclusion of unwanted ion species of higher ionization potential. Also described is a method of producing selected ions from a compound, such as P{sup +} from PH{sub 3}. The invention comprises a plasma chamber, an electron source, a means for introducing a gas to be ionized by electrons from the electron source, means for limiting electron energy from the electron source to a value between the ionization energy of the selected ion species and the greater ionization energy of an unwanted ion specie, and means for extracting the target ion specie from the plasma chamber. In one embodiment, the electrons are generated in a plasma cathode chamber immediately adjacent to the plasma chamber. A small extractor draws the electrons from the plasma cathode chamber into the relatively positive plasma chamber. The energy of the electrons extracted in this manner is easily controlled. The invention is particularly useful for doping silicon with P{sup +}, As{sup +}, and B{sup +} without the problematic presence of hydrogen, helium, water, or carbon oxide ions. Doped silicon is important for manufacture of semiconductors and semiconductor devices. 6 figs.

  11. Free-Electron Laser | Jefferson Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    vacuum ultraviolet light, and is also a source of Terahertz light. The FEL uses electrons to produce laser light. The electrons are energized using the lab's superconducting...

  12. Laser plasma x-ray source for ultrafast time-resolved x-ray absorption spectroscopy

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Miaja-Avila, L.; O'Neil, G. C.; Uhlig, J.; Cromer, C. L.; Dowell, M. L.; Jimenez, R.; Hoover, A. S.; Silverman, K. L.; Ullom, J. N.

    2015-03-02

    We describe a laser-driven x-ray plasma source designed for ultrafast x-ray absorption spectroscopy. The source is comprised of a 1 kHz, 20 W, femtosecond pulsed infrared laser and a water target. We present the x-ray spectra as a function of laser energy and pulse duration. Additionally, we investigate the plasma temperature and photon flux as we vary the laser energy. We obtain a 75 ?m FWHM x-ray spot size, containing ~106 photons/s, by focusing the produced x-rays with a polycapillary optic. Since the acquisition of x-ray absorption spectra requires the averaging of measurements from >107 laser pulses, we also presentmore »data on the source stability, including single pulse measurements of the x-ray yield and the x-ray spectral shape. In single pulse measurements, the x-ray flux has a measured standard deviation of 8%, where the laser pointing is the main cause of variability. Further, we show that the variability in x-ray spectral shape from single pulses is low, thus justifying the combining of x-rays obtained from different laser pulses into a single spectrum. Finally, we show a static x-ray absorption spectrum of a ferrioxalate solution as detected by a microcalorimeter array. Altogether, our results demonstrate that this water-jet based plasma source is a suitable candidate for laboratory-based time-resolved x-ray absorption spectroscopy experiments.« less

  13. Laser-Driven Shock Compression Studies of Planetary Compositions

    E-Print Network [OSTI]

    Spaulding, Dylan Kenneth

    2010-01-01

    2 µm of Au and a 10-12 µm polyimide (CH) ablation layer, astypically a vapor-deposited polyimide-type plastic (CH), 10-

  14. Sinterable powders from laser driven reactions : final report

    E-Print Network [OSTI]

    Haggerty, John Scarseth

    1981-01-01

    Extremely fine, uniform ceramic powders have been synthesized from Sil4 NH3 and C2H4 gas phase reactants that are heated by absorbing optical energy emitted from a C02 laser. Resulting Si, Si3N4 and SiC powders have been ...

  15. Science, technology, and the industrialization of laser-driven processes

    SciTech Connect (OSTI)

    Davis, J.I.; Paisner, J.A.

    1985-05-01

    Members of the laser program at Lawrence Livermore National Laboratory (LLNL) reviewed potential applications of lasers in industry, some of which are: isotope separation; cleanup of radioactive waste; trace impurity removal; selective chemical reactions; photochemical activation or dissociation of gases; control of combustion particulates; crystal and powder chemistry; and laser induced biochemistry. Many of these areas are currently under active study in the community. The investigation at LLNL focused on laser isotope separation of atomic uranium because of the large demand (> 1000 tonnes/year) and high product enrichment price (> $600/kg of product) for material used as fuel in commercial light-water nuclear power reactors. They also believed that once the technology was fully developed and deployed, it could be applied directly to separating many elements economically on an industrial scale. The Atomic Vapor Laser Isotope Separation (AVLIS) program at LLNL has an extensive uranium and plutonium program of >$100 M in FY85 and a minor research program for other elements. This report describes the AVLIS program conducted covering the following topics; candidate elements; separative work units; spectroscopic selectivety; major systems; facilities; integrated process model;multivariable sensitivety studies; world market; and US enrichment enterprise. 23 figs. (AT)

  16. Characterization of Heat-Wave Propagation through Laser-Driven...

    Office of Scientific and Technical Information (OSTI)

    W-7405-ENG-48 Resource Type: Journal Article Resource Relation: Journal Name: High Energy Density Physics, vol. 6, no. 1, November 25, 2009, pp. 89-94; Journal Volume: 6;...

  17. Using laser-driven neutrons to stop nuclear smugglers

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-Inspired SolarAbout /Two0 - 19PortalStatusUserUserHomeUsingUsingbbcpUsing

  18. Effect of the plasma electrode position and shape on the beam intensity of the highly charged ions from RIKEN 18 GHz electron-cyclotron-resonance ion source

    SciTech Connect (OSTI)

    Higurashi, Y.; Nakagawa, T.; Kidera, M.; Aihara, T.; Kobayashi, K.; Kase, M.; Goto, A.; Yano, Y. [RIKEN, Hirosawa 2-1, Wako, Saitama 351-0198 (Japan); SAS Ltd. Kita-shinagawa 5-9-11, Shinjuku-ku, Tokyo (Japan); RIKEN, Hirosawa 2-1, Wako, Saitama 351-0198 (Japan)

    2006-03-15

    Beam intensities of highly charged Ar ions (Ar{sup 11+,12+}) were measured as a function of plasma electrode position. We observed that the beam intensity of Ar{sup 11+,12+} increased when putting the electrode far from the electron-cyclotron-resonance zone. On the other hand, lower charged heavy ions (Ar{sup 8+,7+}) dramatically decreased. We observed that the intense beam extraction strongly affects the plasma condition. It may be due to the ion pumping effect.

  19. Influence of microwave driver coupling design on plasma density at Testbench for Ion sources Plasma Studies, a 2.45 GHz Electron Cyclotron Resonance Plasma Reactor

    SciTech Connect (OSTI)

    Megía-Macías, A.; Vizcaíno-de-Julián, A. [E.S.S. Bilbao, Edificio Cosimet, Landabarri 2, 48940-Leioa, Vizcaya (Spain)] [E.S.S. Bilbao, Edificio Cosimet, Landabarri 2, 48940-Leioa, Vizcaya (Spain); Cortázar, O. D., E-mail: dcortazar@essbilbao.org [E.S.S. Bilbao, Edificio Cosimet, Landabarri 2, 48940-Leioa, Vizcaya (Spain); Universidad de Castilla-La Mancha, ETSII, C.J. Cela s/n, 13170 Ciudad Real (Spain)

    2014-03-15

    A comparative study of two microwave driver systems (preliminary and optimized) for a 2.45 GHz hydrogen Electron Cyclotron Resonance plasma generator has been conducted. The influence on plasma behavior and parameters of stationary electric field distribution in vacuum, i.e., just before breakdown, along all the microwave excitation system is analyzed. 3D simulations of resonant stationary electric field distributions, 2D simulations of external magnetic field mapping, experimental measurements of incoming and reflected power, and electron temperature and density along the plasma chamber axis have been carried out. By using these tools, an optimized set of plasma chamber and microwave coupler has been designed paying special attention to the optimization of stationary electric field value in the center of the plasma chamber. This system shows a strong stability on plasma behavior allowing a wider range of operational parameters and even sustaining low density plasma formation without external magnetic field. In addition, the optimized system shows the capability to produce values of plasma density four times higher than the preliminary as a consequence of a deeper penetration of the magnetic resonance surface in relative high electric field zone by keeping plasma stability. The increment of the amount of resonance surface embedded in the plasma under high electric field is suggested as a key factor.

  20. Improved negative ion source

    DOE Patents [OSTI]

    Delmore, J.E.

    1984-05-01

    A method and apparatus for providing a negative ion source accelerates electrons away from a hot filament electron emitter into a region of crossed electric and magnetic fields arranged in a magnetron configuration. During a portion of the resulting cycloidal path, the electron velocity is reduced below its initial value. The electron accelerates as it leaves the surface at a rate of only slightly less than if there were no magnetic field, thereby preventing a charge buildup at the surface of the emitter. As the electron traverses the cycloid, it is decelerated during the second, third, and fourth quadrants, then reaccelerated as it approaches the end of the fourth quadrant to regain its original velocity. The minimum velocity occurs during the fourth quadrant, and corresponds to an electron temperature of 200 to 500/sup 0/C for the electric and magnetic fields commonly encountered in the ion sources of magnetic sector mass spectrometers. An ion source using the above-described thermalized electrons is also disclosed.

  1. Negative ion source

    DOE Patents [OSTI]

    Delmore, James E. (Idaho Falls, ID)

    1987-01-01

    A method and apparatus for providing a negative ion source accelerates electrons away from a hot filament electron emitter into a region of crossed electric and magnetic fields arranged in a magnetron configuration. During a portion of the resulting cycloidal path, the electron velocity is reduced below its initial value. The electron accelerates as it leaves the surface at a rate of only slightly less than if there were no magnetic field, thereby preventing a charge buildup at the surface of the emitter. As the electron traverses the cycloid, it is decelerated during the second, third, and fourth quadrants, then reeccelerated as it approaches the end of the fourth quadrant to regain its original velocity. The minimum velocity occurs during the fourth quadrant, and corresponds to an electron temperature of 200.degree. to 500.degree. for the electric and magnetic fields commonly encountered in the ion sources of magnetic sector mass spectrometers. An ion source using the above-described thermalized electrons is also disclosed.

  2. Two-frequency heating technique at the 18 GHz electron cyclotron resonance ion source of the National Institute of Radiological Sciences

    SciTech Connect (OSTI)

    Biri, S., E-mail: biri@atomki.hu [National Institute of Radiological Science (NIRS), 4-9-1 Anagawa, Inage, Chiba 263-8555 (Japan); Institute for Nuclear Research (ATOMKI), H-4026 Debrecen, Bem tér 18/c (Hungary); Kitagawa, A.; Muramatsu, M.; Drentje, A. G. [National Institute of Radiological Science (NIRS), 4-9-1 Anagawa, Inage, Chiba 263-8555 (Japan)] [National Institute of Radiological Science (NIRS), 4-9-1 Anagawa, Inage, Chiba 263-8555 (Japan); Rácz, R. [Institute for Nuclear Research (ATOMKI), H-4026 Debrecen, Bem tér 18/c (Hungary)] [Institute for Nuclear Research (ATOMKI), H-4026 Debrecen, Bem tér 18/c (Hungary); Yano, K.; Kato, Y. [Graduated School of Engineering, Osaka University, 2-1 Yamada-oka, Suita-shi, Osaka 565-0871 (Japan)] [Graduated School of Engineering, Osaka University, 2-1 Yamada-oka, Suita-shi, Osaka 565-0871 (Japan); Sasaki, N.; Takasugi, W. [Accelerator Engineering Corporation (AEC), Inage, Chiba 263-0043 (Japan)] [Accelerator Engineering Corporation (AEC), Inage, Chiba 263-0043 (Japan)

    2014-02-15

    The two-frequency heating technique was studied to increase the beam intensities of highly charged ions provided by the high-voltage extraction configuration (HEC) ion source at the National Institute of Radiological Sciences (NIRS). The observed dependences on microwave power and frequency suggested that this technique improved plasma stability but it required precise frequency tuning and more microwave power than was available before 2013. Recently, a new, high-power (1200 W) wide band-width (17.1–18.5 GHz) travelling-wave-tube amplifier (TWTA) was installed. After some single tests with klystron and TWT amplifiers the simultaneous injection of the two microwaves has been successfully realized. The dependence of highly charged ions (HCI) currents on the superposed microwave power was studied by changing only the output power of one of the two amplifiers, alternatively. While operating the klystron on its fixed 18.0 GHz, the frequency of the TWTA was swept within its full limits (17.1–18.5 GHz), and the effect of this frequency on the HCI-production rate was examined under several operation conditions. As an overall result, new beam records of highly charged argon, krypton, and xenon beams were obtained at the NIRS-HEC ion source by this high-power two-frequency operation mode.

  3. Compact x-ray source and panel

    DOE Patents [OSTI]

    Sampayon, Stephen E. (Manteca, CA)

    2008-02-12

    A compact, self-contained x-ray source, and a compact x-ray source panel having a plurality of such x-ray sources arranged in a preferably broad-area pixelized array. Each x-ray source includes an electron source for producing an electron beam, an x-ray conversion target, and a multilayer insulator separating the electron source and the x-ray conversion target from each other. The multi-layer insulator preferably has a cylindrical configuration with a plurality of alternating insulator and conductor layers surrounding an acceleration channel leading from the electron source to the x-ray conversion target. A power source is connected to each x-ray source of the array to produce an accelerating gradient between the electron source and x-ray conversion target in any one or more of the x-ray sources independent of other x-ray sources in the array, so as to accelerate an electron beam towards the x-ray conversion target. The multilayer insulator enables relatively short separation distances between the electron source and the x-ray conversion target so that a thin panel is possible for compactness. This is due to the ability of the plurality of alternating insulator and conductor layers of the multilayer insulators to resist surface flashover when sufficiently high acceleration energies necessary for x-ray generation are supplied by the power source to the x-ray sources.

  4. Microwave ion source

    DOE Patents [OSTI]

    Leung, Ka-Ngo; Reijonen, Jani; Thomae, Rainer W.

    2005-07-26

    A compact microwave ion source has a permanent magnet dipole field, a microwave launcher, and an extractor parallel to the source axis. The dipole field is in the form of a ring. The microwaves are launched from the middle of the dipole ring using a coaxial waveguide. Electrons are heated using ECR in the magnetic field. The ions are extracted from the side of the source from the middle of the dipole perpendicular to the source axis. The plasma density can be increased by boosting the microwave ion source by the addition of an RF antenna. Higher charge states can be achieved by increasing the microwave frequency. A xenon source with a magnetic pinch can be used to produce intense EUV radiation.

  5. Two-frequency heating technique at the 18 GHz electron cyclotron resonance ion source of the National Institute of Radiological Sciences

    E-Print Network [OSTI]

    Biri, S; Muramatsu, M; Drentje, A G; Rácz, R; Yano, K; Kato, Y; Sasaki, N; Takasugi, W

    2015-01-01

    The two-frequency heating technique was studied to increase the beam intensities of highly charged ions provided by the high-voltage extraction configuration (HEC) ion source at the National Institute of Radiological Sciences (NIRS). The observed dependences on microwave power and frequency suggested that this technique improved plasma stability but it required precise frequency tuning and more microwave power than was available before 2013. Recently, a new, high-power (1200 W) wide bandwidth (17.1-18.5 GHz) travelling-wave-tube amplifier (TWTA) was installed. After some single tests with klystron and TWT amplifiers the simultaneous injection of the two microwaves has been successfully realized. The dependence of highly charged ions (HCI) currents on the superposed microwave power was studied by changing only the output power of one of the two amplifiers, alternatively. While operating the klystron on its fixed 18.0 GHz, the frequency of the TWTA was swept within its full limits (17.1-18.5 GHz), and the effec...

  6. THE SYSTEM OF POWER SUPPLIES, CONTROL AND MODULATION OF ELECTRON GUN FOR FREE ELECTRON LASER

    E-Print Network [OSTI]

    Kozak, Victor R.

    THE SYSTEM OF POWER SUPPLIES, CONTROL AND MODULATION OF ELECTRON GUN FOR FREE ELECTRON LASER E of the system. Proceedings of RUPAC2012, Saint|-|Petersburg, Russia TUPPB050 Ion sources and electron guns ISBN

  7. R&D for a Soft X-Ray Free Electron Laser Facility

    E-Print Network [OSTI]

    Staples, John

    2009-01-01

    resolution electron beam diagnostics. • Radiation protectionelectron source, beam instrumentation and diagnostics andand diagnostics equipment to characterize the electron beam.

  8. Analytical Model for Rates of Electron Attachment and Intramolecular Electron Transfer in Electron Transfer

    E-Print Network [OSTI]

    Simons, Jack

    . As a result, in ECD the primary source of excess energy is the recombination energy released when the electron) where free low-energy electrons rather than anion collision partners are used to effect the initial) experiments, one subjects a mass-to-charge-selected parent ion to very low-energy electrons (often boiled off

  9. Electron radiography

    DOE Patents [OSTI]

    Merrill, Frank E.; Morris, Christopher

    2005-05-17

    A system capable of performing radiography using a beam of electrons. Diffuser means receive a beam of electrons and diffuse the electrons before they enter first matching quadrupoles where the diffused electrons are focused prior to the diffused electrons entering an object. First imaging quadrupoles receive the focused diffused electrons after the focused diffused electrons have been scattered by the object for focusing the scattered electrons. Collimator means receive the scattered electrons and remove scattered electrons that have scattered to large angles. Second imaging quadrupoles receive the collimated scattered electrons and refocus the collimated scattered electrons and map the focused collimated scattered electrons to transverse locations on an image plane representative of the electrons' positions in the object.

  10. Focused electron and ion beam systems

    DOE Patents [OSTI]

    Leung, Ka-Ngo; Reijonen, Jani; Persaud, Arun; Ji, Qing; Jiang, Ximan

    2004-07-27

    An electron beam system is based on a plasma generator in a plasma ion source with an accelerator column. The electrons are extracted from a plasma cathode in a plasma ion source, e.g. a multicusp plasma ion source. The beam can be scanned in both the x and y directions, and the system can be operated with multiple beamlets. A compact focused ion or electron beam system has a plasma ion source and an all-electrostatic beam acceleration and focusing column. The ion source is a small chamber with the plasma produced by radio-frequency (RF) induction discharge. The RF antenna is wound outside the chamber and connected to an RF supply. Ions or electrons can be extracted from the source. A multi-beam system has several sources of different species and an electron beam source.

  11. The Linac Coherent Light Source

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    White, William E.; Robert, Aymeric; Dunne, Mike

    2015-05-01

    The Linac Coherent Light Source (LCLS) at the SLAC National Accelerator Laboratory was the first hard X-ray free-electron laser (FEL) to operate as a user facility. After five years of operation, LCLS is now a mature FEL user facility. Our personal views about opportunities and challenges inherent to these unique light sources are discussed.

  12. Diamondoid Monolayers as Monochromatic Electron Source

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submit theCovalent BondingMeeting |DesignCommunitiesYu

  13. Diamondoid Monolayers as Monochromatic Electron Source

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submit theCovalent BondingMeeting |DesignCommunitiesYuDiamondoid Monolayers as

  14. Diamondoid Monolayers as Monochromatic Electron Source

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submit theCovalent BondingMeeting |DesignCommunitiesYuDiamondoid Monolayers

  15. Diamondoid Monolayers as Monochromatic Electron Source

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submit theCovalent BondingMeeting |DesignCommunitiesYuDiamondoid MonolayersDiamondoid

  16. Diamondoid Monolayers as Monochromatic Electron Source

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submit theCovalent BondingMeeting |DesignCommunitiesYuDiamondoid

  17. Diamondoid Monolayers as Monochromatic Electron Source

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    A.A. Fokin (Justus-Liebig University, Germany, and Kiev Polytechnic Institute, Ukraine); and Z. Hussain (ALS). Research funding: U.S. Department of Energy, Office of Basic...

  18. Diamondoid Monolayers as Monochromatic Electron Source

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformation Current HAB Packet HanfordDOEDanielDeSmallDevelopment ofBrowse by

  19. Diamondoid Monolayers as Monochromatic Electron Source

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformation Current HAB Packet HanfordDOEDanielDeSmallDevelopment ofBrowse byDiamondoid

  20. "Title","Creator/Author","Publication Date","OSTI Identifier...

    Office of Scientific and Technical Information (OSTI)

    SPACE 430200* -- Particle Accelerators-- Beam Dynamics, Field Calculations, & Ion Optics",,"The evolution of the electron-beam phase space distribution in laser-driven rf guns...

  1. TITLE AUTHORS SUBJECT SUBJECT RELATED DESCRIPTION PUBLISHER AVAILABILI...

    Office of Scientific and Technical Information (OSTI)

    SPACE PARTICLE BEAMS SPACE Particle Accelerators Beam Dynamics Field Calculations Ion Optics The evolution of the electron beam phase space distribution in laser driven rf guns is...

  2. Intense steady state electron beam generator

    DOE Patents [OSTI]

    Hershcovitch, A.; Kovarik, V.J.; Prelec, K.

    1990-07-17

    An intense, steady state, low emittance electron beam generator is formed by operating a hollow cathode discharge plasma source at critical levels in combination with an extraction electrode and a target electrode that are operable to extract a beam of fast primary electrons from the plasma source through a negatively biased grid that is critically operated to repel bulk electrons toward the plasma source while allowing the fast primary electrons to move toward the target in the desired beam that can be successfully transported for relatively large distances, such as one or more meters away from the plasma source. 2 figs.

  3. Title of Dissertation: LASER SWITCHED ELECTRON BEAM MODULATION WITH TERAHERTZ

    E-Print Network [OSTI]

    Anlage, Steven

    as well as the measurements from the accelerator system. This dissertation demonstrates at terahertz frequencies using laser driven photoemission. It is divided into three distinct areas: laser beam of terahertz radiation. The laser modulation portion covers the development of an interferometer system used

  4. Electronic Spectroscopy of Carbon Chains

    E-Print Network [OSTI]

    Maier, John Paul

    techniques. By employing laser vaporization and pulsed discharge sources, they have created a wide assortment in combustion chemistry, molecular electronics, and the interstellar medium. This review focuses on recent

  5. Electron-Electron Bremsstrahlung Emission and the Inference of Electron Flux Spectra in Solar Flares

    E-Print Network [OSTI]

    Eduard P. Kontar; A. Gordon Emslie; Anna Maria Massone; Michele Piana; John C. Brown; Marco Prato

    2007-07-28

    Although both electron-ion and electron-electron bremsstrahlung contribute to the hard X-ray emission from solar flares, the latter is normally ignored. Such an omission is not justified at electron (and photon) energies above $\\sim 300$ keV, and inclusion of the additional electron-electron bremsstrahlung in general makes the electron spectrum required to produce a given hard X-ray spectrum steeper at high energies. Unlike electron-ion bremsstrahlung, electron-electron bremsstrahlung cannot produce photons of all energies up to the maximum electron energy involved. The maximum possible photon energy depends on the angle between the direction of the emitting electron and the emitted photon, and this suggests a diagnostic for an upper cutoff energy and/or for the degree of beaming of the accelerated electrons. We analyze the large event of January 17, 2005 observed by RHESSI and show that the upward break around 400 keV in the observed hard X-ray spectrum is naturally accounted for by the inclusion of electron-electron bremsstrahlung. Indeed, the mean source electron spectrum recovered through a regularized inversion of the hard X-ray spectrum, using a cross-section that includes both electron-ion and electron-electron terms, has a relatively constant spectral index $\\delta$ over the range from electron kinetic energy $E = 200$ keV to $E = 1$ MeV. However, the level of detail discernible in the recovered electron spectrum is not sufficient to determine whether or not any upper cutoff energy exists.

  6. Free electron laser

    DOE Patents [OSTI]

    Villa, Francesco (Alameda, CA)

    1990-01-01

    A high gain, single-pass free electron laser formed of a high brilliance electron injector source, a linear accelerator which imparts high energy to the electron beam, and an undulator capable of extremely high magnetic fields, yet with a very short period. The electron injector source is the first stage (gap) of the linear accelerator or a radial line transformer driven by fast circular switch. The linear accelerator is formed of a plurality of accelerating gaps arranged in series. These gaps are energized in sequence by releasing a single pulse of energy which propagates simultaneously along a plurality of transmission lines, each of which feeds the gaps. The transmission lines are graduated in length so that pulse power is present at each gap as the accelerated electrons pass therethrough. The transmission lines for each gap are open circuited at their ends. The undualtor has a structure similar to the accelerator, except that the transmission lines for each gap are substantially short circuited at their ends, thus converting the electric field into magnetic field. A small amount of resistance is retained in order to generate a small electric field for replenishing the electron bunch with the energy lost as it traverses through the undulator structure.

  7. Solenoid and monocusp ion source

    DOE Patents [OSTI]

    Brainard, John Paul (Albuquerque, NM); Burns, Erskine John Thomas (Albuquerque, NM); Draper, Charles Hadley (Albuquerque, NM)

    1997-01-01

    An ion source which generates hydrogen ions having high atomic purity incorporates a solenoidal permanent magnets to increase the electron path length. In a sealed envelope, electrons emitted from a cathode traverse the magnetic field lines of a solenoid and a monocusp magnet between the cathode and a reflector at the monocusp. As electrons collide with gas, the molecular gas forms a plasma. An anode grazes the outer boundary of the plasma. Molecular ions and high energy electrons remain substantially on the cathode side of the cusp, but as the ions and electrons are scattered to the aperture side of the cusp, additional collisions create atomic ions. The increased electron path length allows for smaller diameters and lower operating pressures.

  8. Solenoid and monocusp ion source

    DOE Patents [OSTI]

    Brainard, J.P.; Burns, E.J.T.; Draper, C.H.

    1997-10-07

    An ion source which generates hydrogen ions having high atomic purity incorporates a solenoidal permanent magnets to increase the electron path length. In a sealed envelope, electrons emitted from a cathode traverse the magnetic field lines of a solenoid and a monocusp magnet between the cathode and a reflector at the monocusp. As electrons collide with gas, the molecular gas forms a plasma. An anode grazes the outer boundary of the plasma. Molecular ions and high energy electrons remain substantially on the cathode side of the cusp, but as the ions and electrons are scattered to the aperture side of the cusp, additional collisions create atomic ions. The increased electron path length allows for smaller diameters and lower operating pressures. 6 figs.

  9. Wisconsin SRF Electron Gun Commissioning

    SciTech Connect (OSTI)

    Bisognano, Joseph J.; Bissen, M.; Bosch, R.; Efremov, M.; Eisert, D.; Fisher, M.; Green, M.; Jacobs, K.; Keil, R.; Kleman, K.; Rogers, G.; Severson, M.; Yavuz, D. D.; Legg, Robert A.; Bachimanchi, Ramakrishna; Hovater, J. Curtis; Plawski, Tomasz; Powers, Thomas J.

    2013-12-01

    The University of Wisconsin has completed fabrication and commissioning of a low frequency (199.6 MHz) superconducting electron gun based on a quarter wave resonator (QWR) cavity. Its concept was optimized to be the source for a CW free electron laser facility. The gun design includes active tuning and a high temperature superconducting solenoid. We will report on the status of the Wisconsin SRF electron gun program, including commissioning experience and first beam measurements.

  10. Three chamber negative ion source

    DOE Patents [OSTI]

    Leung, K.N.; Ehlers, K.W.; Hiskes, J.R.

    1983-11-10

    It is an object of this invention provide a negative ion source which efficiently provides a large flux of negatively ionized particles. This invention provides a volume source of negative ions which has a current density sufficient for magnetic fusion applications and has electrons suppressed from the output. It is still another object of this invention to provide a volume source of negative ions which can be electrostatically accelerated to high energies and subsequently neutralized to form a high energy neutral beam for use with a magnetically confined plasma.

  11. Photon Source Parameters

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformationJesseworkSURVEYI/OPerformance andAreaPhotoinduced electron transferPhoton Source

  12. Filtered cathodic arc source

    DOE Patents [OSTI]

    Falabella, S.; Sanders, D.M.

    1994-01-18

    A continuous, cathodic arc ion source coupled to a macro-particle filter capable of separation or elimination of macro-particles from the ion flux produced by cathodic arc discharge is described. The ion source employs an axial magnetic field on a cathode (target) having tapered sides to confine the arc, thereby providing high target material utilization. A bent magnetic field is used to guide the metal ions from the target to the part to be coated. The macro-particle filter consists of two straight solenoids, end to end, but placed at 45[degree] to one another, which prevents line-of-sight from the arc spot on the target to the parts to be coated, yet provides a path for ions and electrons to flow, and includes a series of baffles for trapping the macro-particles. 3 figures.

  13. Homegrown solution for synchrotron light source | The Ames Laboratory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and powerful facility. Concerned that this would leave him without the low-energy light source he needed to study the electronic properties of new materials, he improvised,...

  14. Electronic imaging system and technique

    DOE Patents [OSTI]

    Bolstad, J.O.

    1984-06-12

    A method and system for viewing objects obscurred by intense plasmas or flames (such as a welding arc) includes a pulsed light source to illuminate the object, the peak brightness of the light reflected from the object being greater than the brightness of the intense plasma or flame; an electronic image sensor for detecting a pulsed image of the illuminated object, the sensor being operated as a high-speed shutter; and electronic means for synchronizing the shutter operation with the pulsed light source.

  15. Electronic imaging system and technique

    DOE Patents [OSTI]

    Bolstad, Jon O. (Idaho Falls, ID)

    1987-01-01

    A method and system for viewing objects obscurred by intense plasmas or flames (such as a welding arc) includes a pulsed light source to illuminate the object, the peak brightness of the light reflected from the object being greater than the brightness of the intense plasma or flame; an electronic image sensor for detecting a pulsed image of the illuminated object, the sensor being operated as a high-speed shutter; and electronic means for synchronizing the shutter operation with the pulsed light source.

  16. Rippled beam free electron laser amplifier

    DOE Patents [OSTI]

    Carlsten, Bruce E. (Los Alamos, NM)

    1999-01-01

    A free electron laser amplifier provides a scalloping annular electron beam that interacts with the axial electric field of a TM.sub.0n mode. A waveguide defines an axial centerline and, a solenoid arranged about the waveguide produces an axial constant magnetic field within the waveguide. An electron beam source outputs a annular electron beam that interacts with the axial magnetic field to have an equilibrium radius and a ripple radius component having a variable radius with a ripple period along the axial centerline. An rf source outputs an axial electric field that propagates within the waveguide coaxial with the electron beam and has a radial mode that interacts at the electron beam at the equilibrium radius component of the electron beam.

  17. Simulation and measurement of air generated electron contamination in radiotherapy

    E-Print Network [OSTI]

    Yu, Peter K.N.

    Simulation and measurement of air generated electron contamination in radiotherapy Martin J and (ii) electrons produced outside the patient but inci- dent on the patient (electron contamination). To evaluate electron contamination produced by the air column located between the x-ray source and the patient

  18. Europium oxide as a perfect electron spin filter

    E-Print Network [OSTI]

    Santos, Tiffany S. (Tiffany Suzanne), 1980-

    2007-01-01

    Essential to the emergence of spin-based electronics is a source of highly polarized electron spins. Conventional ferromagnets have at best a spin polarization P-50%. Europium monoxide is a novel material capable of ...

  19. MEMS multi-pole electromagnets: Compact electron optics and undulators

    E-Print Network [OSTI]

    Harrison, Jere Charles

    2014-01-01

    electron laser system using MEMS optics . . . . . . . . .power soft x-ray source based on a 400-µm period MEMS un-micrograph of a MEMS ‘racetrack’ transformer. . . . . . .

  20. Effects of non-local electron transport in one-dimensional and two-dimensional simulations of shock-ignited inertial confinement fusion targets

    SciTech Connect (OSTI)

    Marocchino, A.; Atzeni, S.; Schiavi, A. [Dipartimento SBAI, Università di Roma “La Sapienza” and CNISM, Roma 00161 (Italy)] [Dipartimento SBAI, Università di Roma “La Sapienza” and CNISM, Roma 00161 (Italy)

    2014-01-15

    In some regions of a laser driven inertial fusion target, the electron mean-free path can become comparable to or even longer than the electron temperature gradient scale-length. This can be particularly important in shock-ignited (SI) targets, where the laser-spike heated corona reaches temperatures of several keV. In this case, thermal conduction cannot be described by a simple local conductivity model and a Fick's law. Fluid codes usually employ flux-limited conduction models, which preserve causality, but lose important features of the thermal flow. A more accurate thermal flow modeling requires convolution-like non-local operators. In order to improve the simulation of SI targets, the non-local electron transport operator proposed by Schurtz-Nicolaï-Busquet [G. P. Schurtz et al., Phys. Plasmas 7, 4238 (2000)] has been implemented in the DUED fluid code. Both one-dimensional (1D) and two-dimensional (2D) simulations of SI targets have been performed. 1D simulations of the ablation phase highlight that while the shock profile and timing might be mocked up with a flux-limiter; the electron temperature profiles exhibit a relatively different behavior with no major effects on the final gain. The spike, instead, can only roughly be reproduced with a fixed flux-limiter value. 1D target gain is however unaffected, provided some minor tuning of laser pulses. 2D simulations show that the use of a non-local thermal conduction model does not affect the robustness to mispositioning of targets driven by quasi-uniform laser irradiation. 2D simulations performed with only two final polar intense spikes yield encouraging results and support further studies.

  1. Electron tube

    DOE Patents [OSTI]

    Suyama, Motohiro (Hamamatsu, JP); Fukasawa, Atsuhito (Hamamatsu, JP); Arisaka, Katsushi (Los Angeles, CA); Wang, Hanguo (North Hills, CA)

    2011-12-20

    An electron tube of the present invention includes: a vacuum vessel including a face plate portion made of synthetic silica and having a surface on which a photoelectric surface is provided, a stem portion arranged facing the photoelectric surface and made of synthetic silica, and a side tube portion having one end connected to the face plate portion and the other end connected to the stem portion and made of synthetic silica; a projection portion arranged in the vacuum vessel, extending from the stem portion toward the photoelectric surface, and made of synthetic silica; and an electron detector arranged on the projection portion, for detecting electrons from the photoelectric surface, and made of silicon.

  2. 570 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 16, NO. 5, OCTOBER 1988 A Reflex Electron Beam Discharge as a Plasma

    E-Print Network [OSTI]

    Rocca, Jorge J.

    570 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 16, NO. 5, OCTOBER 1988 A Reflex Electron Beam Discharge as a Plasma Source for Electron Beam Generation Abstract-A reflex electron beam glow discharge has been used as a plasma source for the generation of broad-area electron beams. An electron current

  3. Contaminant Sources are Known

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Sources are Known Historical contaminant sources from liquid discharges and solid waste management units are known. August 1, 2013 Contaminant source map LANL contaminant...

  4. Electronic Fireflies

    E-Print Network [OSTI]

    Hacker, Randi; Greene, Megan

    2009-01-28

    . The Japanese: firefly connection goes back to the 8th Century when poets used them to represent human passions. But pollution and development have depleted the number of fireflies. So what's a New Year's reveler to do? Buy Denshi Hotaru, life-sized, electronic...

  5. Electronic Relaxation Dynamics in Coupled Metal Nanoparticles

    E-Print Network [OSTI]

    Scherer, Norbert F.

    that takes into account two competing phenomena: electron inelastic surface scattering (ISS), which tends the ultrafast response to optical excitation. For example, they have promise as optical switches and as sources of hot electrons for photoelectrochemical processes, including solar energy conversion or organic waste

  6. Ultra-bright pulsed electron beam with low longitudinal emittance

    DOE Patents [OSTI]

    Zolotorev, Max (Oakland, CA)

    2010-07-13

    A high-brightness pulsed electron source, which has the potential for many useful applications in electron microscopy, inverse photo-emission, low energy electron scattering experiments, and electron holography has been described. The source makes use of Cs atoms in an atomic beam. The source is cycled beginning with a laser pulse that excites a single Cs atom on average to a band of high-lying Rydberg nP states. The resulting valence electron Rydberg wave packet evolves in a nearly classical Kepler orbit. When the electron reaches apogee, an electric field pulse is applied that ionizes the atom and accelerates the electron away from its parent ion. The collection of electron wave packets thus generated in a series of cycles can occupy a phase volume near the quantum limit and it can possess very high brightness. Each wave packet can exhibit a considerable degree of coherence.

  7. Consumer Electronics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submit the followingConcentrating SolarConstruction Review BasicConsumer-Electronics

  8. Electron Transfer

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submitKansas Nuclear ProfileMultiferroicAward |ElectronFluctuations3 Pierre

  9. Polyplanar optical display electronics

    SciTech Connect (OSTI)

    DeSanto, L.; Biscardi, C.

    1997-07-01

    The Polyplanar Optical Display (POD) is a unique display screen which can be used with any projection source. The prototype ten inch display is two inches thick and has a matte black face which allows for high contrast images. The prototype being developed is a form, fit and functional replacement display for the B-52 aircraft which uses a monochrome ten-inch display. In order to achieve a long lifetime, the new display uses a 100 milliwatt green solid-state laser (10,000 hr. life) at 532 nm as its light source. To produce real-time video, the laser light is being modulated by a Digital Light Processing (DLP{trademark}) chip manufactured by Texas Instruments. In order to use the solid-state laser as the light source and also fit within the constraints of the B-52 display, the Digital Micromirror Device (DMD{trademark}) circuit board is removed from the Texas Instruments DLP light engine assembly. Due to the compact architecture of the projection system within the display chassis, the DMD{trademark} chip is operated remotely from the Texas Instruments circuit board. The authors discuss the operation of the DMD{trademark} divorced from the light engine and the interfacing of the DMD{trademark} board with various video formats (CVBS, Y/C or S-video and RGB) including the format specific to the B-52 aircraft. A brief discussion of the electronics required to drive the laser is also presented.

  10. Single-Shot Femtosecond Electron Diffraction with Laser-Accelerated Electrons: Experimental Demonstration of Electron Pulse Compression

    SciTech Connect (OSTI)

    Tokita, Shigeki; Hashida, Masaki; Inoue, Shunsuke; Nishoji, Toshihiko; Otani, Kazuto; Sakabe, Shuji [Advanced Research Center for Beam Science, Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan and Department of Physics, Graduate School of Science, Kyoto University, Kitashirakawa, Sakyo, Kyoto 606-7501 (Japan)

    2010-11-19

    We report the first experimental demonstration of longitudinal compression of laser-accelerated electron pulses. Accelerated by a femtosecond laser pulse with an intensity of 10{sup 18} W/cm{sup 2}, an electron pulse with an energy of around 350 keV and a relative momentum spread of about 10{sup -2} was compressed to a 500-fs pulse at a distance of about 50 cm from the electron source by using a magnetic pulse compressor. This pulse was used to generate a clear diffraction pattern of a gold crystal in a single shot. This method solves the space-charge problem in ultrafast electron diffraction.

  11. Electronic Coupling Dependence of Ultrafast Interfacial Electron...

    Office of Scientific and Technical Information (OSTI)

    Electron Transfer on Nanocrystalline Thin Films and Single Crystal Lian, Tianquan 14 SOLAR ENERGY The long-term goal of the proposed research is to understand electron transfer...

  12. Tevatron Electron Lenses: Design and Operation

    SciTech Connect (OSTI)

    Shiltsev, Vladimir; Bishofberger, Kip; Kamerdzhiev, Vsevolod; Kozub, Sergei; Kufer, Matthew; Kuznetsov, Gennady; Martinez, Alexander; Olson, Marvin; Pfeffer, Howard; Saewert, Greg; Scarpine, Vic; /Fermilab /SLAC /Fermilab /Serpukhov, IHEP /Novosibirsk, IYF /Serpukhov, IHEP /Fermilab

    2008-08-01

    The beam-beam effects have been the dominating sources of beam loss and lifetime limitations in the Tevatron proton-antiproton collider [1]. Electron lenses were originally proposed for compensation of electromagnetic long-range and head-on beam-beam interactions of proton and antiproton beams [2]. Results of successful employment of two electron lenses built and installed in the Tevatron are reported in [3,4,5]. In this paper we present design features of the Tevatron electron lenses (TELs), discuss the generation of electron beams, describe different modes of operation and outline the technical parameters of various subsystems.

  13. Title of Dissertation: LONGITUDINAL DYNAMICS OF AN INTENSE ELECTRON BEAM

    E-Print Network [OSTI]

    Anlage, Steven

    ABSTRACT Title of Dissertation: LONGITUDINAL DYNAMICS OF AN INTENSE ELECTRON BEAM John Richardson fusion, spallation neutron sources, free-electron lasers, and other applications. In addition, all beams beams. #12;LONGITUDINAL DYNAMICS OF AN INTENSE ELECTRON BEAM By John Richardson Harris. Dissertation

  14. Lithium ion sources

    E-Print Network [OSTI]

    Roy, Prabir K.

    2014-01-01

    HIFAN 1866 Lithium ion sources by Prabir K. Roy, Wayne G.No. DE-AC02-05CH11231. Lithium ion sources Prabir K. Roya source of ?100 mA lithium ion current for the Neutralized

  15. W.A. SERDIJN: "A CLASSIFICATION OF ELECTRONIC SIGNAL-PROCESSING FUNCTIONS" 1 A classification of electronic signal-processing

    E-Print Network [OSTI]

    Serdijn, Wouter A.

    W.A. SERDIJN: "A CLASSIFICATION OF ELECTRONIC SIGNAL-PROCESSING FUNCTIONS" 1 A classification classification of electronic signal-processing functions is proposed. Electronic signals can either be 1 sources, wave- shaping circuits, digital logic functions, digital memories, power supplies, and converters

  16. Single shot ultrafast dynamic ellipsometry (UDE) of laser-driven shocks in single crystal explosives

    SciTech Connect (OSTI)

    Whitley, Von H; Mcgrane, Shawn D; Moore, David S; Eakins, Dan E; Bolme, Cindy A

    2009-01-01

    We report on the first experiments to measure states in shocked energetic single crystals with dynamic ellipsometry. We demonstrate that these ellipsometric techniques can produce reasonable Hugoniot values using small amounts of crystalline RDX and PETN. Pressures, particle velocities and shock velocities obtained using shocked ellipsometry are comparable to those found using gas-gun flyer plates and molecular dynamics calculations. The adaptation of the technique from uniform thin films of polymers to thick non-perfect crystalline materials was a significant achievement. Correct sample preparation proved to be a crucial component. Through trial and error, we were able to resolve polishing issues, sample quality problems, birefringence effects and mounting difficulties that were not encountered using thin polymer films.

  17. Quantification of Uncertainties Due to Opacities in a Laser-Driven Radiative-Shock Problem 

    E-Print Network [OSTI]

    Hetzler, Adam C

    2013-03-28

    This research presents new physics-based methods to estimate predictive uncertainty stemming from uncertainty in the material opacities in radiative transfer computations of key quantities of interest (QOIs). New methods ...

  18. Laser-Driven Shock Acceleration of Ion Beams from Spherical Mass-Limited Targets

    SciTech Connect (OSTI)

    Henig, A.; Kiefer, D.; Hoerlein, R.; Major, Zs.; Krausz, F.; Habs, D. [Max-Planck-Institut fuer Quantenoptik, Garching (Germany); Department fuer Physik, Ludwig-Maximilians-Universitaet Muenchen, Garching (Germany); Geissler, M. [Max-Planck-Institut fuer Quantenoptik, Garching (Germany); Department of Physics and Astronomy, Queen's University Belfast, Belfast BT7 1NN (United Kingdom); Rykovanov, S. G. [Max-Planck-Institut fuer Quantenoptik, Garching (Germany); Moscow Physics Engineering Institute, Kashirskoe shosse 31, Moscow (Russian Federation); Ramis, R. [ETSI Aeronauticos, Universidad Politecnica de Madrid (Spain); Osterhoff, J.; Veisz, L.; Karsch, S. [Max-Planck-Institut fuer Quantenoptik, Garching (Germany); Schreiber, J. [Max-Planck-Institut fuer Quantenoptik, Garching (Germany); Department fuer Physik, Ludwig-Maximilians-Universitaet Muenchen, Garching (Germany); Blackett Laboratory, Imperial College, London SW7 2AZ (United Kingdom)

    2009-03-06

    We report on experimental studies of ion acceleration from spherical targets of diameter 15 {mu}m irradiated by ultraintense (1x10{sup 20} W/cm{sup 2}) pulses from a 20-TW Ti:sapphire laser system. A highly directed proton beam with plateau-shaped spectrum extending to energies up to 8 MeV is observed in the laser propagation direction. This beam arises from acceleration in a converging shock launched by the laser, which is confirmed by 3-dimensional particle-in-cell simulations. The temporal evolution of the shock-front curvature shows excellent agreement with a two-dimensional radiation pressure model.

  19. Laser-Driven Magnetic-Flux Compression in High-Energy-Density Plasmas

    E-Print Network [OSTI]

    Gotchev, O. V.

    The demonstration of magnetic field compression to many tens of megagauss in cylindrical implosions of inertial confinement fusion targets is reported for the first time. The OMEGA laser [T.?R. Boehly et al., Opt. Commun. ...

  20. Measurement of reduced backscattering noise in laser-driven fiber optic gyroscopes

    E-Print Network [OSTI]

    Fan, Shanhui

    (FOG) built with an air-core fiber. Its phase noise is measured to be 130 rad/ Hz. When the sensing-driven air-core FOG will drop below the level of current FOGs. Compared with commercial FOGs, this FOG-optic gyroscope (FOG) is a well-developed, highly stable, and sensitive device that has been com- mercially

  1. Multiscale modeling of beryllium: quantum mechanics and laser-driven shock experiments using novel diagnostics.

    SciTech Connect (OSTI)

    Swift, D. C.; Paisley, Dennis L.; Kyrala, George A.; Hauer, Allan

    2002-01-01

    Ab initio quantum mechanics was used to construct a thermodynamically complete and rigorous equation of state for beryllium in the hexagonal and body-centred cubic structures, and to predict elastic constants as a function of compression. The equation of state agreed well with Hugoniot data and previously-published equations of state, but the temperatures were significantly different. The hexagonal/bcc phase boundary agreed reasonably well with published data, suggesting that the temperatures in our new equation of state were accurate. Shock waves were induced in single crystals and polycrystalline foils of beryllium, by direct illumination using the TRIDENT laser at Los Alamos. The velocity history at the surface of the sample was measured using a line-imaging VISAR, and transient X-ray diffraction (TXD) records were obtained with a plasma backlighter and X-ray streak cameras. The VISAR records exhibited elastic precursors, plastic waves, phase changes and spall. Dual TXD records were taken, in Bragg and Laue orientations. The Bragg lines moved in response to compression in the uniaxial direction. Because direct laser drive was used, the results had to be interpreted with the aid of radiation hydrodynamics simulations to predict the loading history for each laser pulse. In the experiments where there was evidence of polymorphism in the VISAR record, additional lines appeared in the Bragg and Laue records. The corresponding pressures were consistent with the phase boundary predicted by the quantum mechanical equation of state for beryllium. A model of the response of a single crystal of beryllium to shock loading is being developed using these new theoretical and experimental results. This model will be used in meso-scale studies of the response of the microstructure, allowing us to develop a more accurate representation of the behaviour of polycrystalline beryllium.

  2. Experimental method for laser-driven flyer plates for 1-D shocks

    SciTech Connect (OSTI)

    Paisley, D. L.; Luo, S. N.; Swift, D. C.; Loomis, E.; Johnson, R.; Greenfield, S.; Peralta, P.; Koskelo, A.; Tonks, D.

    2007-12-12

    One-dimensional shocks can be generated by impacting flyer plates accelerated to terminal velocities by a confined laser-ablated plasma. Over the past few years, we have developed this capability with our facility-size laser, TRIDENT, capable of {>=}500 Joules at multi-microsecond pulse lengths to accelerate 1-D flyer plates, 8-mm diameter by 0.1-2 mm thick. Plates have been accelerated to terminal velocities of 100 to {>=}500 m/s, with full recovery of the flyer and target for post mortem metallography. By properly tailoring the laser temporal and spatial profile, the expanding confined plasma accelerates the plate away from the transparent sapphire substrate, and decouples the laser parameters from shock pressure profile resulting from the plate impact on a target. Since the flyer plate is in free flight on impact with the target, minimal collateral damage occurs to either. The experimental method to launch these plates to terminal velocity, ancillary diagnostics, and representative experimental data is presented.

  3. Nonlinear pulse propagation and phase velocity of laser-driven plasma waves

    E-Print Network [OSTI]

    Schroeder, Carl B.

    2011-01-01

    of California. Nonlinear pulse propagation and phasea relativistically-intense short-pulse laser in un- derdenseinvestigated in the broad pulse limit, including the e?ects

  4. Research and Development Assessments for Prometheus eavy Ion and Laser Driven Inertial Fusion Energy Reactor Designs

    E-Print Network [OSTI]

    Abdou, Mohamed

    -ion and laser drivers. INTRODUCTION Two commercial central station electric power plants have been conceptually designed and analyzed in the Prometheus[11study led by McDonnell Douglas Aerospace. These plants use reactors, (2) provide programmatic-decision makers with a list of important R&D tasks that need

  5. Research and Development Assessments for Prometheus Heavy Ion and Laser Driven Inertial Fusion Energy Reactor Designs

    E-Print Network [OSTI]

    Tillack, Mark

    station electric power plants have been conceptually designed and analyzed in the Prometheus[1] study led by McDonnell Douglas Aerospace. These plants use inertial fusion energy (IFE) technologies by employing with a list of important R&D tasks that need to be conducted, and (3) identify areas of R&D that are common

  6. Radiation transport and energetics of laser-driven half-hohlraums at the National Ignition Facility

    SciTech Connect (OSTI)

    Moore, A. S. [Directorate Science and Technology, AWE Aldermaston, Reading (United Kingdom); Cooper, A. B.R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Schneider, M. B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); MacLaren, S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Graham, P. [Directorate Science and Technology, AWE Aldermaston, Reading (United Kingdom); Lu, K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Seugling, R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Satcher, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Klingmann, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Comley, A. J. [Directorate Science and Technology, AWE Aldermaston, Reading (United Kingdom); Marrs, R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); May, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Widmann, K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Glendinning, G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Castor, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Sain, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Back, C. A. [General Atomics, San Diego, CA (United States); Hund, J. [General Atomics, San Diego, CA (United States); Baker, K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hsing, W. W. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Foster, J. [Directorate Science and Technology, AWE Aldermaston, Reading (United Kingdom); Young, B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Young, P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2014-06-01

    Experiments that characterize and develop a high energy-density half-hohlraum platform for use in bench-marking radiation hydrodynamics models have been conducted at the National Ignition Facility (NIF). Results from the experiments are used to quantitatively compare with simulations of the radiation transported through an evolving plasma density structure, colloquially known as an N-wave. A half-hohlraum is heated by 80 NIF beams to a temperature of 240 eV. This creates a subsonic di#11;usive Marshak wave which propagates into a high atomic number Ta2O5 aerogel. The subsequent radiation transport through the aerogel and through slots cut into the aerogel layer is investigated. We describe a set of experiments that test the hohlraum performance and report on a range

  7. PHYSICAL REVIEW E 91, 013101 (2015) Integrated simulation approach for laser-driven fast ignition

    E-Print Network [OSTI]

    Wang, Wei Hua

    2015-01-01

    to realize laser fusion energy, the fast ignition (FI) scheme has attracted significant attention since

  8. Twenty times lower ignition threshold for laser driven fusion using collective effects and the inhibition factor

    SciTech Connect (OSTI)

    Hora, H. [Department of Theoretical Physics, University of New South Wales, Sydney 2052 (Australia); Malekynia, B.; Ghoranneviss, M. [Plasma Physics Research Center, Science and Research Branch, Islamic Azad University, Tehran-Poonak 14835-159 (Iran, Islamic Republic of); Miley, G. H. [Department of Nuclear, Plasma and Radiological Engineering, University of Illinois, Urbana, Illinois 61801 (United States); He, X. [Institute of Applied Physics and Computational Mathematics, Beijing 100088 (China)

    2008-07-07

    Hydrodynamic analysis for ignition of inertial fusion by Chu [Phys. Fluids 15, 413 (1972)] arrived at extremely high thresholds of a minimum energy flux density E* at 4x10{sup 8} J/cm{sup 2} which could be provided, e.g., by spark ignition. In view of alternative schemes of fast ignition, a re-evaluation of the early analysis including later discovered collective stopping power and the inhibition factor results in a 20 times lowering of the threshold for E*.

  9. Laser-driven proton fast ignition of inertial fusion: concepts, issues and prospects

    SciTech Connect (OSTI)

    Badziak, J.; Jablonski, S.; Wolowski, J. [Institute of Plasma Physics and Laser Microfusion, Hery 23, 01-497 Warsaw (Poland); Honrubia, J. [GIFI, Universidad Politecnica de Madrid, Madrid (Spain)

    2008-03-19

    Fast ignition (FI) is a novel approach to inertial confinement fusion, which has the potential for higher energy gain at lower overall driver energy and cost. This paper is a brief review of basic FI concepts and issues, with a particular emphasis on FI with laser-generated proton beams. General requirements for the DT fuel and the ignitor (particle beam) as well as for the laser drivers are discussed. Key issues related to proton FI are considered and selected results of experimental and numerical studies are described. A progress in development of laser facilities for FI research and prospects for FI experiments are outlined.

  10. Coherent superposition of laser-driven soft-X-ray harmonics from successive

    E-Print Network [OSTI]

    Loss, Daniel

    the absorption length4,5 , leading to the production of microjoule-energy coherent extreme-ultraviolet pulses6 Institut EP1, Universit¨at W¨urzburg, D-97074 W¨urzburg, Germany 3 Department f¨ur Physik, Ludwig-Maximilians-Universit¨at M¨unchen, D-85748 Garching, Germany 4 Atominstitut der ¨Osterreichischen Universtit¨aten, Technische

  11. Exploring laser-driven quantum phenomena from a time-frequency analysis perspective: A comprehensive study

    E-Print Network [OSTI]

    Sheu, Yae-lin; Hsu, Liang-Yan

    2015-01-01

    Time-frequency (TF) analysis is a powerful tool for exploring ultrafast dynamics in atoms and molecules. While some TF methods have demonstrated their usefulness and potential in several of quantum systems, a systematic comparison among these methods is still lacking. To this end, we compare a series of classical and contemporary TF methods by taking hydrogen atom in a strong laser field as a benchmark. In addition, several TF methods such as Cohen class distribution other than the Wigner-Ville distribution, reassignment methods, and the empirical mode decomposition method are first introduced to exploration of ultrafast dynamics. Among these TF methods, the synchrosqueezing transform successfully illustrates the physical mechanisms in the multiphoton ionization regime and in the tunneling ionization regime. Furthermore, an empirical procedure to analyze an unknown complicated quantum system is provided, indicating the versatility of TF analysis as a new viable venue for exploring quantum dynamics.

  12. First time nuclear material detection by one short-pulse-laser-driven

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformation Current HABFES OctoberEvanServices »First Observation ofFirst in-situ

  13. Characterization of Heat-Wave Propagation through Laser-Driven Ti-Doped

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing Bacteria (TechnicalTransmission,Textit ChandraSciTech

  14. Characterization of Heat-Wave Propagation through Laser-Driven Ti-Doped

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing Bacteria (TechnicalTransmission,Textit ChandraSciTechUnderdense Plasma (Journal

  15. Sub-100 ps laser-driven dynamic compression of solid deuterium with a ~ 40

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail. (Conference)Feedback System inStatus ofSmall GTPases withfromLeptons(Conference) |μ

  16. Sub-100 ps laser-driven dynamic compression of solid deuterium with a ~ 40

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail. (Conference)Feedback System inStatus ofSmall GTPases withfromLeptons(Conference)

  17. Electrolytes for power sources

    DOE Patents [OSTI]

    Doddapaneni, N.; Ingersoll, D.

    1995-01-03

    Electrolytes are disclosed for power sources, particularly alkaline and acidic power sources, comprising benzene polysulfonic acids and benzene polyphosphonic acids or salts of such acids. 7 figures.

  18. Electrolytes for power sources

    DOE Patents [OSTI]

    Doddapaneni, Narayan (Albuquerque, NM); Ingersoll, David (Albuquerque, NM)

    1995-01-01

    Electrolytes for power sources, particularly alkaline and acidic power sources, comprising benzene polysulfonic acids and benzene polyphosphonic acids or salts of such acids.

  19. X-ray lithography source

    DOE Patents [OSTI]

    Piestrup, Melvin A. (Woodside, CA); Boyers, David G. (Mountain View, CA); Pincus, Cary (Sunnyvale, CA)

    1991-01-01

    A high-intensity, inexpensive X-ray source for X-ray lithography for the production of integrated circuits. Foil stacks are bombarded with a high-energy electron beam of 25 to 250 MeV to produce a flux of soft X-rays of 500 eV to 3 keV. Methods of increasing the total X-ray power and making the cross section of the X-ray beam uniform are described. Methods of obtaining the desired X-ray-beam field size, optimum frequency spectrum and elminating the neutron flux are all described. A method of obtaining a plurality of station operation is also described which makes the process more efficient and economical. The satisfying of these issues makes transition radiation an exellent moderate-priced X-ray source for lithography.

  20. Ion Source Development at the SNS

    SciTech Connect (OSTI)

    Welton, Robert F [ORNL; Desai, Nandishkumar J [ORNL; Han, Baoxi [ORNL; Kenik, Edward A [Oak Ridge National Laboratory (ORNL); Murray Jr, S N [ORNL; Pennisi, Terry R [ORNL; Potter, Kerry G [ORNL; Lang, Bonnie R [ORNL; Santana, Manuel [ORNL; Stockli, Martin P [ORNL

    2011-01-01

    The Spallation Neutron Source (SNS) now routinely operates near 1 MW of beam power on target with a highly-persistent ~38 mA peak current in the linac and an availability of ~90%. The ~1 ms-long, 60 Hz, ~50 mA H- beam pulses are extracted from a Cs-enhanced, multi-cusp, RF-driven, internal-antenna ion source. An electrostatic LEBT (Low Energy Beam Transport) focuses the 65 kV beam into the RFQ accelerator. The ion source and LEBT have normally a combined availability of ~99%. Although much progress has been made over the last years to achieve this level of availability further improvements are desirable. Failures of the internal antenna and occasionally impaired electron dump insulators require several source replacements per year. An attempt to overcome the antenna issues with an AlN external antenna source early in 2009 had to be terminated due to availability issues. This report provides a comprehensive review of the design, experimental history, status, and description of recently updated components and future plans for this ion source. The mechanical design for improved electron dump vacuum feedthroughs is also presented, which is compatible with the baseline and both external antenna ion sources.

  1. Catalog of supersoft X-ray sources

    E-Print Network [OSTI]

    J. Greiner

    2000-05-11

    This catalog comprises an up-to-date (December 1999) list of luminous (>10^36 erg/s), binary supersoft X-ray sources. This electronic version (including the accompannying Web-pages) supersedes the printed version of Greiner (1996).

  2. Photo-stimulated low electron temperature high current diamond film field emission cathode

    DOE Patents [OSTI]

    Shurter; Roger Philips (Los Alamos, NM), Devlin; David James (Santa Fe, NM), Moody; Nathan Andrew (Los Alamos, NM), Taccetti; Jose Martin (Santa Fe, NM), Russell; Steven John (Los Alamos, NM)

    2012-07-24

    An electron source includes a back contact surface having a means for attaching a power source to the back contact surface. The electron source also includes a layer comprising platinum in direct contact with the back contact surface, a composite layer of single-walled carbon nanotubes embedded in platinum in direct contact with the layer comprising platinum. The electron source also includes a nanocrystalline diamond layer in direct contact with the composite layer. The nanocrystalline diamond layer is doped with boron. A portion of the back contact surface is removed to reveal the underlying platinum. The electron source is contained in an evacuable container.

  3. Ion-induced electron emission microscopy

    DOE Patents [OSTI]

    Doyle, Barney L. (Albuquerque, NM); Vizkelethy, Gyorgy (Albuquerque, NM); Weller, Robert A. (Brentwood, TN)

    2001-01-01

    An ion beam analysis system that creates multidimensional maps of the effects of high energy ions from an unfocussed source upon a sample by correlating the exact entry point of an ion into a sample by projection imaging of the secondary electrons emitted at that point with a signal from a detector that measures the interaction of that ion within the sample. The emitted secondary electrons are collected in a strong electric field perpendicular to the sample surface and (optionally) projected and refocused by the electron lenses found in a photon emission electron microscope, amplified by microchannel plates and then their exact position is sensed by a very sensitive X Y position detector. Position signals from this secondary electron detector are then correlated in time with nuclear, atomic or electrical effects, including the malfunction of digital circuits, detected within the sample that were caused by the individual ion that created these secondary electrons in the fit place.

  4. Unraveling resistive versus collisional contributions to relativistic electron beam stopping power in cold-solid and in warm-dense plasmas

    SciTech Connect (OSTI)

    Vauzour, B.; Laboratoire d'Optique Appliquée, ENSTA-CNRS-Ecole Polytechnique, UMR 7639, 91761 Palaiseau ; Debayle, A.; CEA, DAM, DIF, F-91297 Arpajon ; Vaisseau, X.; Hulin, S.; Nicolaï, Ph.; Dorchies, F.; Fourment, C.; D'Humières, E.; Tikhonchuk, V. T.; Santos, J. J.; Schlenvoigt, H.-P.; Baton, S. D.; Yahia, V.; Dipartimento di Fisica, Università di Milano-Bicocca, Milano 20126 ; Honrubia, J. J.; Beg, F. N.; Chawla, S.; Jarrot, L. C.; Benocci, R.; Volpe, L.; and others

    2014-03-15

    We present results on laser-driven relativistic electron beam propagation through aluminum samples, which are either solid and cold or compressed and heated by laser-induced shock. A full numerical description of fast electron generation and transport is found to reproduce the experimental absolute K{sub ?} yield and spot size measurements for varying target thicknesses, and to sequentially quantify the collisional and resistive electron stopping powers. The results demonstrate that both stopping mechanisms are enhanced in compressed Al samples and are attributed to the increase in the medium density and resistivity, respectively. For the achieved time- and space-averaged electronic current density, ?j{sub h}??8×10{sup 10}?A/cm{sup 2} in the samples, the collisional and resistive stopping powers in warm and compressed Al are estimated to be 1.5?keV/?m and 0.8?keV/?m, respectively. By contrast, for cold and solid Al, the corresponding estimated values are 1.1?keV/?m and 0.6?keV/?m. Prospective numerical simulations involving higher j{sub h} show that the resistive stopping power can reach the same level as the collisional one. In addition to the effects of compression, the effect of the transient behavior of the resistivity of Al during relativistic electron beam transport becomes progressively more dominant, and for a significantly high current density, j{sub h}?10{sup 12}?A/cm{sup 2}, cancels the difference in the electron resistive stopping power (or the total stopping power in units of areal density) between solid and compressed samples. Analytical calculations extend the analysis up to j{sub h}=10{sup 14}?A/cm{sup 2} (representative of the full-scale fast ignition scenario of inertial confinement fusion), where a very rapid transition to the Spitzer resistivity regime saturates the resistive stopping power, averaged over the electron beam duration, to values of ?1?keV/?m.

  5. Electron beam generation in Tevatron electron lenses

    SciTech Connect (OSTI)

    Kamerdzhiev, V.; Kuznetsov, G.; Shiltsev, V.; Solyak, N.; Tiunov, M.; /Novosibirsk, IYF

    2006-08-01

    New type of high perveance electron guns with convex cathode has been developed. Three guns described in this article are built to provide transverse electron current density distributions needed for Electron Lenses for beam-beam compensation in the Tevatron collider. The current distribution can be controlled either by the gun geometry or by voltage on a special control electrode located near cathode. We present the designs of the guns and report results of beam measurements on the test bench. Because of their high current density and low transverse temperature of electrons, electron guns of this type can be used in electron cooling and beam-beam compensation devices.

  6. Generation of Femtosecond Electron And Photon Pulses

    SciTech Connect (OSTI)

    Thongbai, C.; Jinamoon, V.; Kangrang, M.; Kusoljariyakul, K.; Rimjaem, S.; Saisut, J.; Vilaithong, T.; Rhodes, M.W.; Wichaisirimongkol, P.; Wiedemann, H.; /SLAC

    2006-03-17

    Femtosecond (fs) electron and photon pulses become a tool of increasing importance to study dynamics in ultrafast processes. Such short electron pulses can be generated from a system consisting of a thermionic-cathode RF-gun and a magnetic bunch compressor. The fs electron pulses can be used directly or used as a source to produce equally short electromagnetic radiation pulses via certain kind of radiation production processes. At the Fast Neutron Research Facility (FNRF), Thailand, we are especially interested in production of radiation in Farinfrared and X-ray regime. In the far-infrared wavelengths, the radiation emitted from fs electron pulses is emitted coherently resulting high intensity radiation. In the X-ray regime, development of fs X-ray sources is crucial for application in ultrafast sciene.

  7. Collisional relaxation of electrons in a warm plasma and accelerated nonthermal electron spectra in solar flares

    E-Print Network [OSTI]

    Kontar, E P; Emslie, A G; Bian, N H

    2015-01-01

    Extending previous studies of nonthermal electron transport in solar flares which include the effects of collisional energy diffusion and thermalization of fast electrons, we present an analytic method to infer more accurate estimates of the accelerated electron spectrum in solar flares from observations of the hard X-ray spectrum. Unlike for the standard cold-target model, the spatial characteristics of the flaring region, especially the necessity to consider a finite volume of hot plasma in the source, need to be taken into account in order to correctly obtain the injected electron spectrum from the source-integrated electron flux spectrum (a quantity straightforwardly obtained from hard X-ray observations). We show that, for a given source-integrated electron flux spectrum, the overall power in the injected electrons could be reduced by an order of magnitude or more relative to its cold-target value. Indeed, the extent of electron thermalization can be significant enough to nullify the need to introduce an...

  8. PUBLISHED ONLINE: 10 OCTOBER 2010 | DOI: 10.1038/NPHYS1790 Modelling loop-top X-ray source and reconnection

    E-Print Network [OSTI]

    Loss, Daniel

    an important role in many plasma phenomena including solar flares3,4 , star formation5 and other astrophysical events6 , laser-driven plasma jets7­9 , and fusion plasma instabilities10 . Because of the large and Technology, Peking University, Beijing 100871, China, 6Institute for Fusion and Simulation, Zhejiang

  9. INSTITUTE OF PHYSICS PUBLISHING PLASMA SOURCES SCIENCE AND TECHNOLOGY Plasma Sources Sci. Technol. 12 (2003) 302312 PII: S0963-0252(03)62087-6

    E-Print Network [OSTI]

    Economou, Demetre J.

    2003-01-01

    INSTITUTE OF PHYSICS PUBLISHING PLASMA SOURCES SCIENCE AND TECHNOLOGY Plasma Sources Sci. Technol pressures (above 20 mTorr), electrons in an ICP discharge are heated by collisional dissipation of wave energy. Power deposition in lower pressure discharges, however, involves a collisionless electron heating

  10. Chapter 9: Electronics

    E-Print Network [OSTI]

    Spieler, Helmuth G

    2008-01-01

    R. Armstrong Contents Electronics 9.1 Introduction 9.2measurements 9.11 Digital electronics 9.11.1 Logic elementsProblems page 1 vii Electronics This chapter was contributed

  11. Laser-PlasmaWakefield Acceleration with Higher Order Laser Modes

    E-Print Network [OSTI]

    Geddes, C.G.R.

    2011-01-01

    Design considerations for a laser-plasma linear collider,"E.Esarey, and W.P.Leemans, "Free-electron laser driven bythe LBNL laser-plasma accelerator," in Proc. Adv. Acc. Con.

  12. Note on RF Photo-Cathode Gun

    E-Print Network [OSTI]

    Kim, Kwang-Je

    2010-01-01

    Emittances in Laser-Driven RF Guns", Proc. 1988 Linear Acc.Palmer, "Preliminary Study of Gun Emittance Correction", BNLLaser-Driven RF Electron Guns", Nuc1. ln stt. Meth. , A275,

  13. Pseudopotential for the electron-electron interaction

    E-Print Network [OSTI]

    Lloyd-Williams, J H; Conduit, G J

    2015-01-01

    We propose a pseudopotential for the electron-electron Coulomb interaction to improve the efficiency of many-body electronic structure calculations. The pseudopotential accurately replicates the scattering properties of the Coulomb interaction, and recovers the analytical solution for two electrons in a parabolic trap. A case study for the homogeneous electron gas using the diffusion Monte Carlo and configuration interaction methods recovers highly accurate values for the ground state energy, and the smoother potential reduces the computational cost by a factor of ~30. Finally, we demonstrate the use of the pseudopotential to study isolated lithium and beryllium atoms.

  14. Controlling Graphene's Electronic Structure

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Controlling Graphene's Electronic Structure Print Wednesday, 25 April 2007 00:00 Graphene, because of its unusual electron properties, reduced dimensionality, and scale, has...

  15. Analysis of 3-panel and 4-panel microscale ionization sources

    SciTech Connect (OSTI)

    Natarajan, Srividya; Parker, Charles B.; Glass, Jeffrey T. [Department of Electrical and Computer Engineering, Duke University, Durham, North Carolina 27708 (United States); Piascik, Jeffrey R.; Gilchrist, Kristin H. [Center for Materials and Electronic Technologies, RTI International, Research Triangle Park, North Carolina 27709 (United States); Stoner, Brian R. [Department of Electrical and Computer Engineering, Duke University, Durham, North Carolina 27708 (United States); Center for Materials and Electronic Technologies, RTI International, Research Triangle Park, North Carolina 27709 (United States)

    2010-06-15

    Two designs of a microscale electron ionization (EI) source are analyzed herein: a 3-panel design and a 4-panel design. Devices were fabricated using microelectromechanical systems technology. Field emission from carbon nanotube provided the electrons for the EI source. Ion currents were measured for helium, nitrogen, and xenon at pressures ranging from 10{sup -4} to 0.1 Torr. A comparison of the performance of both designs is presented. The 4-panel microion source showed a 10x improvement in performance compared to the 3-panel device. An analysis of the various factors affecting the performance of the microion sources is also presented. SIMION, an electron and ion optics software, was coupled with experimental measurements to analyze the ion current results. The electron current contributing to ionization and the ion collection efficiency are believed to be the primary factors responsible for the higher efficiency of the 4-panel microion source. Other improvements in device design that could lead to higher ion source efficiency in the future are also discussed. These microscale ion sources are expected to find application as stand alone ion sources as well as in miniature mass spectrometers.

  16. Ponderomotive phase plate for transmission electron microscopes

    DOE Patents [OSTI]

    Reed, Bryan W. (Livermore, CA)

    2012-07-10

    A ponderomotive phase plate system and method for controllably producing highly tunable phase contrast transfer functions in a transmission electron microscope (TEM) for high resolution and biological phase contrast imaging. The system and method includes a laser source and a beam transport system to produce a focused laser crossover as a phase plate, so that a ponderomotive potential of the focused laser crossover produces a scattering-angle-dependent phase shift in the electrons of the post-sample electron beam corresponding to a desired phase contrast transfer function.

  17. Ultrafast X-ray Sources

    SciTech Connect (OSTI)

    George Neil

    2010-04-19

    Since before the scattering of X-rays off of DNA led to the first understanding of the double helix structure, sources of X-rays have been an essential tool for scientists examining the structure and interactions of matter. The resolution of a microscope is proportional to the wavelength of light so x-rays can see much finer structures than visible light, down to single atoms. In addition, the energy of X-rays is resonant with the core atomic levels of atoms so with appropriate wavelengths the placement of specific atoms in a large molecule can be determined. Over 10,000 scientists use synchrotron sources, storage rings of high energy electrons, each year worldwide. As an example of such use, virtually every picture of a protein or drug molecule that one sees in the scientific press is a reconstruction based on X-ray scattering of synchrotron light from the crystallized form of that molecule. Unfortunately those pictures are static and proteins work through configuration (shape) changes in response to energy transfer. To understand how biological systems work requires following the energy flow to these molecules and tracking how shape changes drive their interaction with other molecules. We'd like to be able to freeze the action of these molecules at various steps along the way with an X-ray strobe light. How fast does it have to be? To actually get a picture of a molecule in a fixed configuration requires X-ray pulses as short as 30 femtoseconds (1/30 of a millionth of a millionth of a second). To capture the energy flow through changes in electronic levels requires a faster strobe, less than 1 femtosecond! And to acquire such information in smaller samples with higher accuracy demands brighter and brighter X-rays. Unfortunately modern synchrotrons (dubbed 3rd Generation Light Sources) cannot deliver such short bright pulses of X-rays. An entirely new approach is required, linear-accelerator (linac-)-based light sources termed 4th or Next Generation Light Sources (NGLSs). Although NGLSs will not displace synchrotrons from their role they do offer exciting new capabilities which can be understood from the physics of the light production in each device.

  18. Portable thermo-photovoltaic power source

    DOE Patents [OSTI]

    Zuppero, Anthony C. (Idaho Falls, ID); Krawetz, Barton (Idaho Falls, ID); Barklund, C. Rodger (Idaho Falls, ID); Seifert, Gary D. (Idaho Falls, ID)

    1997-01-14

    A miniature thermo-photovoltaic (TPV) device for generation of electrical power for use in portable electronic devices. A TPV power source is constructed to provide a heat source chemical reactor capable of using various fuels, such as liquid hydrocarbons, including but not limited to propane, LPG, butane, alcohols, oils and diesel fuels to generate a source of photons. A reflector dish guides misdirected photon energy from the photon source toward a photovoltaic array. A thin transparent protector sheet is disposed between the photon source and the array to reflect back thermal energy that cannot be converted to electricity, and protect the array from thermal damage. A microlens disposed between the protector sheet and the array further focuses the tailored band of photon energy from the photon source onto an array of photovoltaic cells, whereby the photon energy is converted to electrical power. A heat recuperator removes thermal energy from reactor chamber exhaust gases, preferably using mini- or micro-bellows to force air and fuel past the exhaust gases, and uses the energy to preheat the fuel and oxidant before it reaches the reactor, increasing system efficiency. Mini- or micro-bellows force ambient air through the system both to supply oxidant and to provide cooling. Finally, an insulator, which is preferably a super insulator, is disposed around the TPV power source to reduce fuel consumption, and to keep the TPV power source cool to the touch so it can be used in hand-held devices.

  19. Coronal electron confinement by double layers

    SciTech Connect (OSTI)

    Li, T. C.; Drake, J. F.; Swisdak, M.

    2013-12-01

    In observations of flare-heated electrons in the solar corona, a longstanding problem is the unexplained prolonged lifetime of the electrons compared to their transit time across the source. This suggests confinement. Recent particle-in-cell (PIC) simulations, which explored the transport of pre-accelerated hot electrons through ambient cold plasma, showed that the formation of a highly localized electrostatic potential drop, in the form of a double layer (DL), significantly inhibited the transport of hot electrons. The effectiveness of confinement by a DL is linked to the strength of the DL as defined by its potential drop. In this work, we investigate the scaling of the DL strength with the hot electron temperature by PIC simulations and find a linear scaling. We demonstrate that the strength is limited by the formation of parallel shocks. Based on this, we analytically determine the maximum DL strength, and also find a linear scaling with the hot electron temperature. The DL strength obtained from the analytic calculation is comparable to that from the simulations. At the maximum strength, the DL is capable of confining a significant fraction of hot electrons in the source.

  20. Magnetized Cascade Arc Source forMagnetized Cascade Arc Source for Ionization and Fuelling in TCSUIonization and Fuelling in TCSU

    E-Print Network [OSTI]

    Washington at Seattle, University of

    , the arc source can also be run during FRC sustainment to provide steady state plasma fuelling. The deuterium plasma produced by the arc source is tied to the external axial magnetic field lines, providing and is used for initial breakdown and arc sustainment. Plasma densities of 1020 m-3 and electron temperatures

  1. Electron Beam Production by Pyroelectric Crystals

    E-Print Network [OSTI]

    James D. Brownridge; Stephen M. Shafroth

    2002-09-20

    Pyroelectric crystals are used to produce self-focused electron beams with energies greater than 170 keV. No high voltage power supply or electron gun is needed. The system works by simply changing the temperature of a crystal of LiNbO3 or LiTaO3 by about 100oC in dilute gas. Electron beam energy spectra as well as positive-ion-beam energy spectra and profiles are shown. A change in the crystal temperature of 100oC will cause a spontaneous change in polarization. The change in polarization will be manifested by a change in charge on the surface of the crystal. It is this uncompensated charge that produces the electric field, which accelerates the electrons, or the positive ions and gives rise to the plasma, which in turn focuses them. The source of the accelerated electrons or positive ions is gas molecules ionized near the crystal surface. When the crystal surface is negative electrons are accelerated away from it and positive ions are attracted to the surface. These positive ions reduce the net negative charge on the surface thereby reducing the electric field, which causes the electron energy to decrease over time even though the focal properties remain unchanged. When the surface is positive the reverse obtains and the positive ion beam energy decreases over time as well. We will present video clips, photographic and electronic data that demonstrate many of the characteristics and applications of these electron beams.

  2. Compton backscattered collmated X-ray source

    DOE Patents [OSTI]

    Ruth, Ronald D. (Woodside, CA); Huang, Zhirong (Stanford, CA)

    2000-01-01

    A high-intensity, inexpensive and collimated x-ray source for applications such as x-ray lithography is disclosed. An intense pulse from a high power laser, stored in a high-finesse resonator, repetitively collides nearly head-on with and Compton backscatters off a bunched electron beam, having relatively low energy and circulating in a compact storage ring. Both the laser and the electron beams are tightly focused and matched at the interaction region inside the optical resonator. The laser-electron interaction not only gives rise to x-rays at the desired wavelength, but also cools and stabilizes the electrons against intrabeam scattering and Coulomb repulsion with each other in the storage ring. This cooling provides a compact, intense bunch of electrons suitable for many applications. In particular, a sufficient amount of x-rays can be generated by this device to make it an excellent and flexible Compton backscattered x-ray (CBX) source for high throughput x-ray lithography and many other applications.

  3. Compton backscattered collimated x-ray source

    DOE Patents [OSTI]

    Ruth, R.D.; Huang, Z.

    1998-10-20

    A high-intensity, inexpensive and collimated x-ray source is disclosed for applications such as x-ray lithography is disclosed. An intense pulse from a high power laser, stored in a high-finesse resonator, repetitively collides nearly head-on with and Compton backscatters off a bunched electron beam, having relatively low energy and circulating in a compact storage ring. Both the laser and the electron beams are tightly focused and matched at the interaction region inside the optical resonator. The laser-electron interaction not only gives rise to x-rays at the desired wavelength, but also cools and stabilizes the electrons against intrabeam scattering and Coulomb repulsion with each other in the storage ring. This cooling provides a compact, intense bunch of electrons suitable for many applications. In particular, a sufficient amount of x-rays can be generated by this device to make it an excellent and flexible Compton backscattered x-ray (CBX) source for high throughput x-ray lithography and many other applications. 4 figs.

  4. Compton backscattered collimated x-ray source

    DOE Patents [OSTI]

    Ruth, Ronald D. (Woodside, CA); Huang, Zhirong (Stanford, CA)

    1998-01-01

    A high-intensity, inexpensive and collimated x-ray source for applications such as x-ray lithography is disclosed. An intense pulse from a high power laser, stored in a high-finesse resonator, repetitively collides nearly head-on with and Compton backscatters off a bunched electron beam, having relatively low energy and circulating in a compact storage ring. Both the laser and the electron beams are tightly focused and matched at the interaction region inside the optical resonator. The laser-electron interaction not only gives rise to x-rays at the desired wavelength, but also cools and stabilizes the electrons against intrabeam scattering and Coulomb repulsion with each other in the storage ring. This cooling provides a compact, intense bunch of electrons suitable for many applications. In particular, a sufficient amount of x-rays can be generated by this device to make it an excellent and flexible Compton backscattered x-ray (CBX) source for high throughput x-ray lithography and many other applications.

  5. DC source assemblies

    DOE Patents [OSTI]

    Campbell, Jeremy B; Newson, Steve

    2013-02-26

    Embodiments of DC source assemblies of power inverter systems of the type suitable for deployment in a vehicle having an electrically grounded chassis are provided. An embodiment of a DC source assembly comprises a housing, a DC source disposed within the housing, a first terminal, and a second terminal. The DC source also comprises a first capacitor having a first electrode electrically coupled to the housing, and a second electrode electrically coupled to the first terminal. The DC source assembly further comprises a second capacitor having a first electrode electrically coupled to the housing, and a second electrode electrically coupled to the second terminal.

  6. ELECTRONIC CHARTS INTRODUCTION

    E-Print Network [OSTI]

    New Hampshire, University of

    199 CHAPTER 14 ELECTRONIC CHARTS INTRODUCTION 1400. The Importance of Electronic Charts Since. Electronic charts automate the process of integrating real-time positions with the chart display and allow is expected to take and plot a fix every three minutes. An electronic chart system can do it once per second

  7. Analysis Of Application Of Electronics In Exploration And Exploitation...

    Open Energy Info (EERE)

    Analysis Of Application Of Electronics In Exploration And Exploitation Of Geothermal-Energy Sources In India Jump to: navigation, search OpenEI Reference LibraryAdd to library...

  8. Light sources based on semiconductor current filaments

    DOE Patents [OSTI]

    Zutavern, Fred J. (Albuquerque, NM); Loubriel, Guillermo M. (Albuquerque, NM); Buttram, Malcolm T. (Sandia Park, NM); Mar, Alan (Albuquerque, NM); Helgeson, Wesley D. (Albuquerque, NM); O'Malley, Martin W. (Edgewood, NM); Hjalmarson, Harold P. (Albuquerque, NM); Baca, Albert G. (Albuquerque, NM); Chow, Weng W. (Cedar Crest, NM); Vawter, G. Allen (Albuquerque, NM)

    2003-01-01

    The present invention provides a new type of semiconductor light source that can produce a high peak power output and is not injection, e-beam, or optically pumped. The present invention is capable of producing high quality coherent or incoherent optical emission. The present invention is based on current filaments, unlike conventional semiconductor lasers that are based on p-n junctions. The present invention provides a light source formed by an electron-hole plasma inside a current filament. The electron-hole plasma can be several hundred microns in diameter and several centimeters long. A current filament can be initiated optically or with an e-beam, but can be pumped electrically across a large insulating region. A current filament can be produced in high gain photoconductive semiconductor switches. The light source provided by the present invention has a potentially large volume and therefore a potentially large energy per pulse or peak power available from a single (coherent) semiconductor laser. Like other semiconductor lasers, these light sources will emit radiation at the wavelength near the bandgap energy (for GaAs 875 nm or near infra red). Immediate potential applications of the present invention include high energy, short pulse, compact, low cost lasers and other incoherent light sources.

  9. Low energy electron irradiation of an apple 

    E-Print Network [OSTI]

    Brescia, Giovanni Batista

    2002-01-01

    simulation. A software package, MCNP (Monte Carlo N-Particle), was used to simulate an electron beam irradiation with a 1.0, 1.5 and 2.0 MeV sources on an apple modeled by interconnecting two spheres. The apple radii were 4.4 cm (perpendicular to its axis...

  10. STUDY OF LASER INJECTION OF ELECTRONS INTO PLASMA C. B. Schroeder, P. B. Lee, J. S. Wurtele, Dept. of Physics, Univ. of California, Berkeley, CA, USA

    E-Print Network [OSTI]

    Wurtele, Jonathan

    STUDY OF LASER INJECTION OF ELECTRONS INTO PLASMA WAKEFIELDS C. B. Schroeder, P. B. Lee, J. S. P. Leemans, LBNL, Berkeley, CA, USA Abstract A proposed laser-plasma based electron source [1] using laser triggered injection of electrons is examined. The source generates ultrashort electron bunches

  11. Free electron laser using Rf coupled accelerating and decelerating structures

    DOE Patents [OSTI]

    Brau, Charles A. (Los Alamos, NM); Swenson, Donald A. (Los Alamos, NM); Boyd, Jr., Thomas J. (Los Alamos, NM)

    1984-01-01

    A free electron laser and free electron laser amplifier using beam transport devices for guiding an electron beam to a wiggler of a free electron laser and returning the electron beam to decelerating cavities disposed adjacent to the accelerating cavities of the free electron laser. Rf energy is generated from the energy depleted electron beam after it emerges from the wiggler by means of the decelerating cavities which are closely coupled to the accelerating cavities, or by means of a second bore within a single set of cavities. Rf energy generated from the decelerated electron beam is used to supplement energy provided by an external source, such as a klystron, to thereby enhance overall efficiency of the system.

  12. Single electron detection and spectroscopy via relativistic cyclotron radiation

    E-Print Network [OSTI]

    D. M. Asner; R. F. Bradley; L. de Viveiros; P. J. Doe; J. L. Fernandes; M. Fertl; E. C. Finn; J. A. Formaggio; D. Furse; A. M. Jones; J. N. Kofron; B. H. LaRoque; M. Leber; E. L. McBride; M. L. Miller; P. Mohanmurthy; B. Monreal; N. S. Oblath; R. G. H. Robertson; L. J Rosenberg; G. Rybka; D. Rysewyk; M. G. Sternberg; J. R. Tedeschi; T. Thummler; B. A. VanDevender; N. L. Woods

    2015-05-01

    It has been understood since 1897 that accelerating charges must emit electromagnetic radiation. Cyclotron radiation, the particular form of radiation emitted by an electron orbiting in a magnetic field, was first derived in 1904. Despite the simplicity of this concept, and the enormous utility of electron spectroscopy in nuclear and particle physics, single-electron cyclotron radiation has never been observed directly. Here we demonstrate single-electron detection in a novel radiofrequency spec- trometer. We observe the cyclotron radiation emitted by individual magnetically-trapped electrons that are produced with mildly-relativistic energies by a gaseous radioactive source. The relativistic shift in the cyclotron frequency permits a precise electron energy measurement. Precise beta elec- tron spectroscopy from gaseous radiation sources is a key technique in modern efforts to measure the neutrino mass via the tritium decay endpoint, and this work demonstrates a fundamentally new approach to precision beta spectroscopy for future neutrino mass experiments.

  13. Dynamic radioactive particle source

    DOE Patents [OSTI]

    Moore, Murray E.; Gauss, Adam Benjamin; Justus, Alan Lawrence

    2012-06-26

    A method and apparatus for providing a timed, synchronized dynamic alpha or beta particle source for testing the response of continuous air monitors (CAMs) for airborne alpha or beta emitters is provided. The method includes providing a radioactive source; placing the radioactive source inside the detection volume of a CAM; and introducing an alpha or beta-emitting isotope while the CAM is in a normal functioning mode.

  14. Plasma wake field XUV radiation source

    DOE Patents [OSTI]

    Prono, Daniel S. (Los Alamos, NM); Jones, Michael E. (Los Alamos, NM)

    1997-01-01

    A XUV radiation source uses an interaction of electron beam pulses with a gas to create a plasma radiator. A flowing gas system (10) defines a circulation loop (12) with a device (14), such as a high pressure pump or the like, for circulating the gas. A nozzle or jet (16) produces a sonic atmospheric pressure flow and increases the density of the gas for interacting with an electron beam. An electron beam is formed by a conventional radio frequency (rf) accelerator (26) and electron pulses are conventionally formed by a beam buncher (28). The rf energy is thus converted to electron beam energy, the beam energy is used to create and then thermalize an atmospheric density flowing gas to a fully ionized plasma by interaction of beam pulses with the plasma wake field, and the energetic plasma then loses energy by line radiation at XUV wavelengths Collection and focusing optics (18) are used to collect XUV radiation emitted as line radiation when the high energy density plasma loses energy that was transferred from the electron beam pulses to the plasma.

  15. Magnetic-cusp, cathodic-arc source

    DOE Patents [OSTI]

    Falabella, Steven (Livermore, CA)

    1995-01-01

    A magnetic-cusp for a cathodic-arc source wherein the arc is confined to the desired cathode surface, provides a current path for electrons from the cathode to the anode, and utilizes electric and magnetic fields to guide ions from the cathode to a point of use, such as substrates to be coated. The magnetic-cusp insures arc stability by an easy magnetic path from anode to cathode, while the straight-through arrangement leads to high ion transmission.

  16. Laboratory Design for High-Performance Electron Microscopy

    E-Print Network [OSTI]

    Knowles, David William

    in the need to construct special laboratories. As resolutions improve, transmission electron microscopes (TEMs) and scanning transmission electron microscopes (STEMs) become more sensitive to ambient conditions. State plenum of air in the HVAC system) and have only the minimum number of heat-producing sources. Similarly

  17. Coherent transition radiation from a helically microbunched electron beam

    SciTech Connect (OSTI)

    Hemsing, E.; Rosenzweig, J. B. [Department of Physics and Astronomy, Particle Beam Physics Laboratory, University of California Los Angeles, Los Angeles, California 90095 (United States)

    2009-05-01

    The coherent transition radiation emitted from an electron beam with higher-order spatial microbunching is analyzed. The characteristic angular and phase dependence can be used to identify the dominant bunching structure of such beams, which can be generated during the harmonic interaction in optical klystron modulators and free-electron lasers, and used as tunable sources of coherent light with orbital angular momentum.

  18. Volumetric plasma source development and characterization.

    SciTech Connect (OSTI)

    Crain, Marlon D. (National Security Technologies, LLC, Las Vegas, NV); Maron, Yitzhak (Weizmann Institute of Science, Rehovot, Israel); Oliver, Bryan Velten; Starbird, Robert L. (National Security Technologies, LLC, Las Vegas, NV); Johnston, Mark D.; Hahn, Kelly Denise; Mehlhorn, Thomas Alan; Droemer, Darryl W. (National Security Technologies, LLC, Las Vegas, NV); National Security Technologies, LLC, Las Vegas, NV

    2008-09-01

    The development of plasma sources with densities and temperatures in the 10{sup 15}-10{sup 17} cm{sup -3} and 1-10eV ranges which are slowly varying over several hundreds of nanoseconds within several cubic centimeter volumes is of interest for applications such as intense electron beam focusing as part of the x-ray radiography program. In particular, theoretical work [1,2] suggests that replacing neutral gas in electron beam focusing cells with highly conductive, pre-ionized plasma increases the time-averaged e-beam intensity on target, resulting in brighter x-ray sources. This LDRD project was an attempt to generate such a plasma source from fine metal wires. A high voltage (20-60kV), high current (12-45kA) capacitive discharge was sent through a 100 {micro}m diameter aluminum wire forming a plasma. The plasma's expansion was measured in time and space using spectroscopic techniques. Lineshapes and intensities from various plasma species were used to determine electron and ion densities and temperatures. Electron densities from the mid-10{sup 15} to mid-10{sup 16} cm{sup -3} were generated with corresponding electron temperatures of between 1 and 10eV. These parameters were measured at distances of up to 1.85 cm from the wire surface at times in excess of 1 {micro}s from the initial wire breakdown event. In addition, a hydrocarbon plasma from surface contaminants on the wire was also measured. Control of these contaminants by judicious choice of wire material, size, and/or surface coating allows for the ability to generate plasmas with similar density and temperature to those given above, but with lower atomic masses.

  19. RHIC electron lenses upgrades

    SciTech Connect (OSTI)

    Gu, X.; Altinbas, Z.; Bruno, D.; Binello, S.; Costanzo, M.; Drees, A.; Fischer, W.; Gassner, D. M.; Hock, J.; Hock, K.; Harvey, M.; Luo, Y.; Marusic, A.; Mi, C.; Mernick, K.; Minty, M.; Michnoff, R.; Miller, T. A.; Pikin, A. I.; Robert-Demolaize, G.; Samms, T.; Shrey, T. C.; Schoefer, V.; Tan, Y.; Than, R.; Thieberger, P.; White, S. M.

    2015-05-03

    In the Relativistic Heavy Ion Collider (RHIC) 100 GeV polarized proton run in 2015, two electron lenses were used to partially compensate for the head-on beam-beam effect for the first time. Here, we describe the design of the current electron lens, detailing the hardware modifications made after the 2014 commissioning run with heavy ions. A new electron gun with 15-mm diameter cathode is characterized. The electron beam transverse profile was measured using a YAG screen and fitted with a Gaussian distribution. During operation, the overlap of the electron and proton beams was achieved using the electron backscattering detector in conjunction with an automated orbit control program.

  20. Radiation Source Replacement Workshop

    SciTech Connect (OSTI)

    Griffin, Jeffrey W.; Moran, Traci L.; Bond, Leonard J.

    2010-12-01

    This report summarizes a Radiation Source Replacement Workshop in Houston Texas on October 27-28, 2010, which provided a forum for industry and researchers to exchange information and to discuss the issues relating to replacement of AmBe, and potentially other isotope sources used in well logging.

  1. Lithium ion sources

    E-Print Network [OSTI]

    Roy, Prabir K.

    2014-01-01

    HIFAN 1866 Lithium ion sources by Prabir K. Roy, Wayne G.No. DE-AC02-05CH11231. Lithium ion sources Prabir K. RoyUSA Abstract A 10.9 cm diameter lithium alumino-silicate ion

  2. Tsunami Sources Icosahedron Globe

    E-Print Network [OSTI]

    Tsunami Sources Icosahedron Globe August 2012 Edition NOAA National Geophysical Data Center World to reduce to 8.5" x 11". This globe of Earth shows the locations of historical tsunami sources, extracted from NGDC'sGlobal Historical Tsunami Database (ngdc.noaa.gov/hazard). A tsunamiisaseriesof traveling

  3. Wide Bandgap Semiconductors for Power Electronics, Optoelectronics, and Advanced Communications

    E-Print Network [OSTI]

    Nair, Sankar

    alternative green energy sources and the development of UV light sources for water purification and biological in our nation's future. Seeing that electrical energy is the fastest growing form of energy used a critical role the future of electronics. Unlike Si, these materials can have bandgaps that are tunable

  4. Visualization of Trajectories of Electron Beams Emitted by an Ion Source with Closed Electron Drift

    E-Print Network [OSTI]

    Bordenjuk, Ian V.; Institue of Physics, National Academy of Sciences of Ukraine

    2008-01-01

    National Academy of Sciences of Ukraine, 46 Nauki Ave. ,Kiev, Ukraine 03028. I.G. Brown is with the LawrenceTechnology Center in Ukraine), Project #118J. Publis her

  5. Imaging Electrons in Few-Electron Quantum Dots

    E-Print Network [OSTI]

    Imaging Electrons in Few-Electron Quantum Dots A thesis presented by Parisa Fallahi to The Division Electrons in Few-Electron Quantum Dots Abstract Electrons in a one-electron quantum dot were imaged the tip-induced shift of the electron energy state in the dot. A technique for extracting the amplitude

  6. Piezotube borehole seismic source

    DOE Patents [OSTI]

    Daley, Tom M; Solbau, Ray D; Majer, Ernest L

    2014-05-06

    A piezoelectric borehole source capable of permanent or semipermanent insertion into a well for uninterrupted well operations is described. The source itself comprises a series of piezoelectric rings mounted to an insulative mandrel internally sized to fit over a section of well tubing, the rings encased in a protective housing and electrically connected to a power source. Providing an AC voltage to the rings will cause expansion and contraction sufficient to create a sonic pulse. The piezoelectric borehole source fits into a standard well, and allows for uninterrupted pass-through of production tubing, and other tubing and electrical cables. Testing using the source may be done at any time, even concurrent with well operations, during standard production.

  7. Catalac free electron laser

    DOE Patents [OSTI]

    Brau, Charles A. (Los Alamos, NM); Swenson, Donald A. (Los Alamos, NM); Boyd, Jr., Thomas J. (Los Alamos, NM)

    1982-01-01

    A catalac free electron laser using a rf linac (catalac) which acts as a catalyst to accelerate an electron beam in an initial pass through the catalac and decelerate the electron beam during a second pass through the catalac. During the second pass through the catalac, energy is extracted from the electron beam and transformed to energy of the accelerating fields of the catalac to increase efficiency of the device. Various embodiments disclose the use of post linacs to add electron beam energy extracted by the wiggler and the use of supplementary catalacs to extract energy at various energy peaks produced by the free electron laser wiggler to further enhance efficiency of the catalac free electron laser. The catalac free electron laser can be used in conjunction with a simple resonator, a ring resonator or as an amplifier in conjunction with a master oscillator laser.

  8. Neutrinos in the Electron

    E-Print Network [OSTI]

    E. L. Koschmieder

    2006-09-26

    We will show that one half of the rest mass of the electron is equal to the sum of the rest masses of electron neutrinos and that the other half of the rest mass of the electron is given by the energy in the sum of electric oscillations. With this composition we can explain the rest mass, the electric charge, the spin and the magnetic moment of the electron.

  9. Electron Beam Lithography

    E-Print Network [OSTI]

    Sandini, Giulio

    Electron Beam Lithography Marco Salerno #12;Outline · general lithographic concepts · EBL www.cnf.cornell.edu/SPIEBook/SPIE1.HTM #12;Typical Electron Beam Column Zeiss GeminiTM column Types of Electron Beam Columns · no e- cross over no Boersch-effect (additional energy spread) · beam booster

  10. Dark Energy and Electrons

    E-Print Network [OSTI]

    Burra G. Sidharth

    2008-08-05

    In the light of recent developments in Dark Energy, we consider the electron in a such a background field and show that at the Compton wavelength the electron is stable, in that the Cassini inward pressure exactly counterbalances the outward Coulomb repulsive pressure thus answering a problem of the earlier electron theory.

  11. Electronics, Electrical Engineering

    E-Print Network [OSTI]

    SCHOOL OF Electronics, Electrical Engineering and Computer Science IS IN YOUR HANDS THE FUTURE #12;SCHOOL OF Electronics, Electrical Engineering and Computer Science2 CAREERS IN ELECTRONICS, ELECTRICAL ENGINEERING AND COMPUTER SCIENCE This is an exciting time to join the School of EEECS at Queen's University

  12. Porous silicon with embedded tritium as a stand-alone prime power source for optoelectronic applications

    DOE Patents [OSTI]

    Tam, S.W.

    1997-02-25

    Disclosed is an illumination source comprising a porous silicon having a source of electrons on the surface and/or interstices thereof having a total porosity in the range of from about 50 v/o to about 90 v/o. Also disclosed are a tritiated porous silicon and a photovoltaic device and an illumination source of tritiated porous silicon. 1 fig.

  13. Porous silicon with embedded tritium as a stand-alone prime power source for optoelectronic applications

    DOE Patents [OSTI]

    Tam, S.W.

    1998-06-16

    An illumination source is disclosed comprising a porous silicon having a source of electrons on the surface and/or interstices thereof having a total porosity in the range of from about 50 v/o to about 90 v/o. Also disclosed are a tritiated porous silicon and a photovoltaic device and an illumination source of tritiated porous silicon. 1 fig.

  14. Electrons from Muon Decay in Bound State

    E-Print Network [OSTI]

    Rashid M. Djilkibaev; Rostislav V. Konoplich

    2009-02-12

    We present results of a study of the muon decay in orbit (DIO) contribution to the signal region of muon - electron conversion. Electrons from DIO are the dominant source of background for muon - electron conversion experiments because the endpoint of DIO electrons is the same as the energy of electrons from elastic muon - electron conversion. The probability of DIO contribution to the signal region was considered for a tracker with Gaussian resolution function and with a realistic resolution function obtained in the application of pattern recognition and momentum reconstruction Kalman filter based procedure to GEANT simulated DIO events. It is found that the existence of non Gaussian tails in the realistic resolution function does not lead to a significant increase in DIO contribution to the signal region. The probability of DIO contribution to the calorimeter signal was studied in dependence on the resolution, assuming a Gaussian resolution function of calorimeter. In this study the geometrical acceptance played an important role, suppressing DIO contribution of the intermediate range electrons from muon decay in orbit.

  15. Microfabricated diffusion source

    DOE Patents [OSTI]

    Oborny, Michael C. (Albuquerque, NM); Frye-Mason, Gregory C. (Cedar Crest, NM); Manginell, Ronald P. (Albuquerque, NM)

    2008-07-15

    A microfabricated diffusion source to provide for a controlled diffusion rate of a vapor comprises a porous reservoir formed in a substrate that can be filled with a liquid, a headspace cavity for evaporation of the vapor therein, a diffusion channel to provide a controlled diffusion of the vapor, and an outlet to release the vapor into a gas stream. The microfabricated diffusion source can provide a calibration standard for a microanalytical system. The microanalytical system with an integral diffusion source can be fabricated with microelectromechanical systems technologies.

  16. Electron Beam for LHC

    E-Print Network [OSTI]

    Mieczyslaw Witold Krasny

    2004-05-13

    A method of delivering a monochromatic electron beam to the LHC interaction points is proposed. In this method, heavy ions are used as carriers of the projectile electrons. Acceleration, storage and collision-stability aspects of such a hybrid beam is discussed and a new beam-cooling method is presented. This discussion is followed by a proposal of the Parasitic Ion-Electron collider at LHC (PIE@LHC). The PIE@LHC provides an opportunity, for the present LHC detectors, to enlarge the scope of their research program by including the program of electron-proton and electron-nucleuscollisions with minor machine and detector investments.

  17. SOLUTION-PROCESSED INORGANIC ELECTRONICS

    E-Print Network [OSTI]

    Bakhishev, Teymur

    2011-01-01

    Conductors for Flexible Electronics,” Journal of Thefor low-cost and flexible electronics. Parts of his workwidespread use in flexible electronics. From an economic

  18. SOLUTION-PROCESSED INORGANIC ELECTRONICS

    E-Print Network [OSTI]

    Bakhishev, Teymur

    2011-01-01

    Solution-Processed Graphene Electronics,” Nano Letters, vol.applications,” Organic Electronics, vol. 12, no. 2, pp. 249-design in organic electronics by dual-gate technology,” in

  19. Galactic Superluminal Sources

    E-Print Network [OSTI]

    B. A. Harmon

    1998-12-21

    A new class of X-ray sources was clearly established with the discovery of highly relativistic radio jets from the galactic sources GRS 1915+105 and GRO J1655-40. Both of these objects have given us a broader view of black holes and the formation of jets, yet they also show the complexity of the accretion environment near relativistic objects. The fast apparent motion of the jets, their luminosity and variability, their high energy spectrum, and approximate scaling to the behavior of active galactic nuclei, certainly warrant the description "microquasar". I present a review of the observational data on these sources, and discuss where we stand on a physical picture of GRS 1915+105 and GRO J1655-40 as taken from multi-wavelength studies. I also point out other galactic sources which share some of the properties of the microquasars, and what to look for as a high energy "signature" in future observations.

  20. Open source hardware

    E-Print Network [OSTI]

    Acosta, Roberto, S.M. Massachusetts Institute of Technology

    2009-01-01

    Open source software development models have created some of the most innovative tools and companies in the industry today modifying the way value is created and businesses developed. The purpose of this thesis is to analyze ...

  1. National Synchrotron Light Source

    ScienceCinema (OSTI)

    None

    2010-01-08

    A tour of Brookhaven's National Synchrotron Light Source (NSLS). The NSLS is one of the world's most widely used scientific research facilities, hosting more than 2,500 guest researchers each year. The NSLS provides intense beams of infrared, ultraviole

  2. Light Source Effects

    E-Print Network [OSTI]

    Forbus, K.

    1977-05-01

    The perception of surface luster in achromatic single view images seems to depend on the existence of regions with source-like properties. These regions are due to the interaction of specular component of the surface's ...

  3. A surface ionization source 

    E-Print Network [OSTI]

    Buzatu, Daniel J.

    1995-01-01

    The main part of the work described herein is the development and testing of a surface ionization source for use on a collinear fast beam laser spectroscopy apparatus. A description of the previously existing fast beam apparatus is given...

  4. Magnetron sputtering source

    DOE Patents [OSTI]

    Makowiecki, Daniel M. (Livermore, WA); McKernan, Mark A. (Livermore, CA); Grabner, R. Fred (Brentwood, CA); Ramsey, Philip B. (Livermore, CA)

    1994-01-01

    A magnetron sputtering source for sputtering coating substrates includes a high thermal conductivity electrically insulating ceramic and magnetically attached sputter target which can eliminate vacuum sealing and direct fluid cooling of the cathode assembly. The magnetron sputtering source design results in greater compactness, improved operating characteristics, greater versatility, and low fabrication cost. The design easily retrofits most sputtering apparatuses and provides for safe, easy, and cost effective target replacement, installation, and removal.

  5. Magnetron sputtering source

    DOE Patents [OSTI]

    Makowiecki, D.M.; McKernan, M.A.; Grabner, R.F.; Ramsey, P.B.

    1994-08-02

    A magnetron sputtering source for sputtering coating substrates includes a high thermal conductivity electrically insulating ceramic and magnetically attached sputter target which can eliminate vacuum sealing and direct fluid cooling of the cathode assembly. The magnetron sputtering source design results in greater compactness, improved operating characteristics, greater versatility, and low fabrication cost. The design easily retrofits most sputtering apparatuses and provides for safe, easy, and cost effective target replacement, installation, and removal. 12 figs.

  6. National Synchrotron Light Source

    ScienceCinema (OSTI)

    BNL

    2009-09-01

    A tour of Brookhaven's National Synchrotron Light Source (NSLS), hosted by Associate Laboratory Director for Light Sources, Stephen Dierker. The NSLS is one of the world's most widely used scientific research facilities, hosting more than 2,500 guest researchers each year. The NSLS provides intense beams of infrared, ultraviolet, and x-ray light for basic and applied research in physics, chemistry, medicine, geophysics, environmental, and materials sciences.

  7. Control and manipulation of electron beams

    SciTech Connect (OSTI)

    Piot, Philippe; /NICADD, DeKalb /Northern Illinois U. /Fermilab

    2008-09-01

    The concepts of the advanced accelerators and light source rely on the production of bright electron beams. The rms areas of the beam phase space often need to be tailored to the specific applications. Furthermore, a new class of the forefront research calls for detailed specific distribution such as the particle density in the time coordinate. Several groups are tackling these various challenges and in this report we attempt to give a review of the state-of-the-art of the control and manipulation of the electron beams.

  8. Electron emission of stripping foil and collimation system for CSNS/RCS

    E-Print Network [OSTI]

    Huang, Ming-Yang; Wang, Na; Wang, Sheng

    2015-01-01

    For the Rapid Cycling Synchrotron of the China Spallation Neutron Source (CSNS/RCS), the electron emission plays an important role in the accelerator limitation. The interactions between the proton beam and the stripping foil were studied, and the electron scattering processes were simulated by the ORBIT and FLUKA codes. Then, the electron energy distribution and the electron yielding rate can be given. Furthermore, the interactions between the proton beam and the collimation system were studied, and the electron scattering processes were simulated. Then, the energy distribution of the primary electron emission can be given and the yielding rate of the primary electron can be obtained.

  9. Electron thermal conductivity owing to collisions between degenerate electrons

    E-Print Network [OSTI]

    P. S. Shternin; D. G. Yakovlev

    2006-08-17

    We calculate the thermal conductivity of electrons produced by electron-electron Coulomb scattering in a strongly degenerate electron gas taking into account the Landau damping of transverse plasmons. The Landau damping strongly reduces this conductivity in the domain of ultrarelativistic electrons at temperatures below the electron plasma temperature. In the inner crust of a neutron star at temperatures T electron conductivity due to electron-ion (electron-phonon) scattering and becomes competitive with the the electron conductivity due to scattering of electrons by impurity ions.

  10. Single-electron shuttle based on a silicon quantum dot

    E-Print Network [OSTI]

    K. W. Chan; M. Mottonen; A. Kemppinen; N. S. Lai; K. Y. Tan; W. H. Lim; A. S. Dzurak

    2011-10-05

    We report on single-electron shuttling experiments with a silicon metal-oxide-semiconductor quantum dot at 300 mK. Our system consists of an accumulated electron layer at the Si/SiO_2 interface below an aluminum top gate with two additional barrier gates used to deplete the electron gas locally and to define a quantum dot. Directional single-electron shuttling from the source and to the drain lead is achieved by applying a dc source-drain bias while driving the barrier gates with an ac voltage of frequency f_p. Current plateaus at integer levels of ef_p are observed up to f_p = 240 MHz operation frequencies. The observed results are explained by a sequential tunneling model which suggests that the electron gas may be heated substantially by the ac driving voltage.

  11. Laser-Produced Coherent X-Ray Sources

    SciTech Connect (OSTI)

    Donald Umstadter

    2007-01-31

    We study the generation of x-rays from the interaction of relativistic electrons with ultra-intense laser pulse either directly or via laser generated ion channels. The laser pulse acts as the accelerator and wiggler leading to an all-optical synchrotron-like x-ray source. The mm sized accelerator and micron-sized wiggler leads to a compact source of high brightness, ultrafast x-rays with applications in relativistic nonlinear optics, ultrafast chemistry, biology, inner-shell electronic processes and phase transitions.

  12. Negative ion source

    DOE Patents [OSTI]

    Leung, Ka-Ngo (Hercules, CA); Ehlers, Kenneth W. (Alamo, CA)

    1984-01-01

    An ionization vessel is divided into an ionizing zone and an extraction zone by a magnetic filter. The magnetic filter prevents high-energy electrons from crossing from the ionizing zone to the extraction zone. A small positive voltage impressed on a plasma grid, located adjacent an extraction grid, positively biases the plasma in the extraction zone to thereby prevent positive ions from migrating from the ionizing zone to the extraction zone. Low-energy electrons, which would ordinarily be dragged by the positive ions into the extraction zone, are thereby prevented from being present in the extraction zone and being extracted along with negative ions by the extraction grid. Additional electrons are suppressed from the output flux using ExB drift provided by permanent magnets and the extractor grid electrical field.

  13. Negative ion source

    DOE Patents [OSTI]

    Leung, K.N.; Ehlers, K.W.

    1984-12-04

    An ionization vessel is divided into an ionizing zone and an extraction zone by a magnetic filter. The magnetic filter prevents high-energy electrons from crossing from the ionizing zone to the extraction zone. A small positive voltage impressed on a plasma grid, located adjacent an extraction grid, positively biases the plasma in the extraction zone to thereby prevent positive ions from migrating from the ionizing zone to the extraction zone. Low-energy electrons, which would ordinarily be dragged by the positive ions into the extraction zone, are thereby prevented from being present in the extraction zone and being extracted along with negative ions by the extraction grid. Additional electrons are suppressed from the output flux using ExB drift provided by permanent magnets and the extractor grid electrical field. 14 figs.

  14. Negative ion source

    DOE Patents [OSTI]

    Leung, K.N.; Ehlers, K.W.

    1982-08-06

    An ionization vessel is divided into an ionizing zone and an extraction zone by a magnetic filter. The magnetic filter prevents high-energy electrons from crossing from the ionizing zone to the extraction zone. A small positive voltage impressed on a plasma grid, located adjacent an extraction grid, positively biases the plasma in the extraction zone to thereby prevent positive ions from migrating from the ionizing zone to the extraction zone. Low-energy electrons, which would ordinarily be dragged by the positive ions into the extraction zone, are thereby prevented from being present in the extraction zone and being extracted along with negative ions by the extraction grid. Additional electrons are suppressed from the output flux using ExB drift provided by permanent magnets and the extractor grid electrical field.

  15. Models of radiofrequency coupling for negative ion sources

    SciTech Connect (OSTI)

    Cavenago, M.; Petrenko, S. [INFN-LNL, viale dell'Universita n.2, 35020 Legnaro (Italy)

    2012-02-15

    Radiofrequency heating for ICP (inductively coupled plasma) ion sources depends on the source operating pressure, the presence or absence of a Faraday shield, the driver coil geometry, the frequency used, and the magnetic field configuration: in negative ion source a magnetic filter seems necessary for H{sup -} survival. The result of single particle simulations showing the possibility of electron acceleration in the preglow regime and for reasonable driver chamber radius (15 cm) is reported, also as a function of the static external magnetic field. An effective plasma conductivity, depending not only from electron density, temperature, and rf field but also on static magnetic field is here presented and compared to previous models. Use of this conductivity and of multiphysics tools for a plasma transport and heating model is shown and discussed for a small source.

  16. Transport of energetic electrons in a magnetically expanding helicon double layer plasma

    SciTech Connect (OSTI)

    Takahashi, Kazunori [Space Plasma, Power and Propulsion Group, Research School of Physics and Engineering, The Australian National University, Canberra 0200 (Australia); Department of Electronic Engineering, Tohoku University, Sendai 980-8579 (Japan); Department of Electrical and Electronic Engineering, Iwate University, Morioka 020-8551 (Japan); Charles, Christine; Boswell, Rod; Cox, Wes [Space Plasma, Power and Propulsion Group, Research School of Physics and Engineering, The Australian National University, Canberra 0200 (Australia); Hatakeyama, Rikizo [Department of Electronic Engineering, Tohoku University, Sendai 980-8579 (Japan)

    2009-05-11

    Peripheral magnetic field lines extending from the plasma source into the diffusion chamber are found to separate two regions of Maxwellian electron energy probability functions: the central, ion-beam containing region with an electron temperature of 5 eV, and region near the chamber walls with electrons at 3 eV. Along the peripheral field lines a bi-Maxwellian population with a hot tail at 9 eV is shown to both originate from electrons in the source traveling downstream across the double layer and correspond to a local maximum in ion and electron densities.

  17. Submillimeter-resolution radiography of shielded structures with laser-accelerated electron beams

    E-Print Network [OSTI]

    Umstadter, Donald

    Submillimeter-resolution radiography of shielded structures with laser-accelerated electron beams (Received 24 March 2010; published 14 October 2010) We investigate the use of energetic electron beams-wakefield accelera- tors have been shown to produce electron beams with source sizes comparable to the laser beam

  18. Counter-Streaming Electron Beams in the Plasma Sheet Associated with Auroral Activity

    E-Print Network [OSTI]

    Fillingim, Matthew

    Counter-Streaming Electron Beams in the Plasma Sheet Associated with Auroral Activity M. Fillingim1 expansion and recovery reveal the presence of counter-streaming electron beams. The beams, which appear in the auroral region show a similar electron spectrum. The source of the field-aligned beams is unknown

  19. Electron cyclotron wave resonance plasma assisted deposition of cubic boron nitride thin films

    E-Print Network [OSTI]

    Zexian, Cao

    Electron cyclotron wave resonance plasma assisted deposition of cubic boron nitride thin films Z. X-pressure plasma source. The electron-cyclotron-wave resonance ECWR plasma served both to sputter the hBN target the high-resolution TEM image and the arc pattern of the 111 reflection from selected-area electron

  20. Betatron radiation based measurement of the electron-beam size in a wakefield accelerator

    SciTech Connect (OSTI)

    Schnell, Michael; Saevert, Alexander; Reuter, Maria; and others

    2012-07-09

    We present a spatial and spectral characterization of a laser-plasma based betatron source which allows us to determine the betatron oscillation amplitude of the electrons which decreases with increasing electron energies. Due to the observed oscillation amplitude and the independently measured x-ray source size of (1.8{+-}0.3){mu}m we are able to estimate the electron bunch diameter to be (1.6{+-}0.3){mu}m.

  1. ECR Ion Source Developments at the Oak Ridge National Laboratory

    SciTech Connect (OSTI)

    Alton, G.D.; Liu, Y.; Meyer, F.W.

    1998-10-05

    New techniques for enhancing the performances of electron cyclotron resonance (ECR) ion sources are being investigated at the Oak Ridge National Laboratory. We have utilized the multiple discrete frequency technique to improve the charge state distributions extracted from conventional magnetic field geometry ECR source by injecting three frequencies into the source. A new flat central magnetic field concept, has been incorporated in the designs of a compact all-permanent-magnet source for high charge-state ion beam generation and a compact electromagnetic source for singly ionized radioactive ion beam generation for use in the Holifield Radioactive Ion Beam Facility (HRIBF) research program. A review of the three frequency injection experiments and descriptions of the design aspects of the "volume-type" ECR ion sources will be given in this report.

  2. Polarized electron beams at milliampere average current

    SciTech Connect (OSTI)

    Poelker, Matthew

    2013-11-01

    This contribution describes some of the challenges associated with developing a polarized electron source capable of uninterrupted days-long operation at milliAmpere average beam current with polarization greater than 80%. Challenges will be presented in the context of assessing the required level of extrapolation beyond the performance of today's CEBAF polarized source operating at ~ 200 uA average current. Estimates of performance at higher current will be based on hours-long demonstrations at 1 and 4 mA. Particular attention will be paid to beam-related lifetime-limiting mechanisms, and strategies to construct a photogun that operate reliably at bias voltage > 350kV.

  3. Pixel array detector for X-ray free electron laser experiments Hugh T. Philipp a,, Marianne Hromalik c

    E-Print Network [OSTI]

    Gruner, Sol M.

    Source (LCLS) at the SLAC National Laboratory [3]. The detector features 14-bit in-pixel digitization Coherent Light Source (LCLS). The PAD was made by fabricating custom CMOS electronics using a commercial 0

  4. Development of a hydraulic borehole seismic source

    SciTech Connect (OSTI)

    Cutler, R.P.

    1998-04-01

    This report describes a 5 year, $10 million Sandia/Industry project to develop an advanced borehole seismic source for use in oil and gas exploration and production. The development Team included Sandia, Chevron, Amoco, Conoco, Exxon, Raytheon, Pelton, and GRI. The seismic source that was developed is a vertically oriented, axial point force, swept frequency, clamped, reaction-mass vibrator design. It was based on an early Chevron prototype, but the new tool incorporates a number of improvements which make it far superior to the original prototype. The system consists of surface control electronics, a special heavy duty fiber optic wireline and draw works, a cablehead, hydraulic motor/pump module, electronics module, clamp, and axial vibrator module. The tool has a peak output of 7,000 lbs force and a useful frequency range of 5 to 800 Hz. It can operate in fluid filled wells with 5.5-inch or larger casing to depths of 20,000 ft and operating temperatures of 170 C. The tool includes fiber optic telemetry, force and phase control, provisions to add seismic receiver arrays below the source for single well imaging, and provisions for adding other vibrator modules to the tool in the future. The project yielded four important deliverables: a complete advanced borehole seismic source system with all associated field equipment; field demonstration surveys funded by industry showing the utility of the system; industrial sources for all of the hardware; and a new service company set up by their industrial partner to provide commercial surveys.

  5. Electron emitting filaments for electron discharge devices

    DOE Patents [OSTI]

    Leung, Ka-Ngo (Hercules, CA); Pincosy, Philip A. (Oakland, CA); Ehlers, Kenneth W. (Alamo, CA)

    1988-01-01

    Electrons are copiously emitted by a device comprising a loop-shaped filament made of lanthanum hexaboride. The filament is directly heated by an electrical current produced along the filament by a power supply connected to the terminal legs of the filament. To produce a filament, a diamond saw or the like is used to cut a slice from a bar made of lanthanum hexaboride. The diamond saw is then used to cut the slice into the shape of a loop which may be generally rectangular, U-shaped, hairpin-shaped, zigzag-shaped, or generally circular. The filaments provide high electron emission at a relatively low operating temperature, such as 1600.degree. C. To achieve uniform heating, the filament is formed with a cross section which is tapered between the opposite ends of the filament to compensate for non-uniform current distribution along the filament due to the emission of electrons from the filament.

  6. Electron emitting filaments for electron discharge devices

    DOE Patents [OSTI]

    Leung, K.N.; Pincosy, P.A.; Ehlers, K.W.

    1983-06-10

    Electrons are copiously emitted by a device comprising a loop-shaped filament made of lanthanum hexaboride. The filament is directly heated by an electrical current produced along the filament by a power supply connected to the terminal legs of the filament. To produce a filament, a diamond saw or the like is used to cut a slice from a bar made of lanthanum hexaboride. The diamond saw is then used to cut the slice into the shape of a loop which may be generally rectangular, U-shaped, hairpin-shaped, zigzag-shaped, or generally circular. The filaments provide high electron emission at a relatively low operating temperature, such as 1600/sup 0/C. To achieve uniform heating, the filament is formed with a cross section which is tapered between the opposite ends of the filament to compensate for nonuniform current distribution along the filament due to the emission of electrons from the filament.

  7. Metamaterials for Ballistic Electrons

    E-Print Network [OSTI]

    Daniela Dragoman; Mircea Dragoman

    2007-01-02

    The paper presents a metamaterial for ballistic electrons, which consists of a quantum barrier formed in a semiconductor with negative effective electron mass. This barrier is the analogue of a metamaterial for electromagnetic waves in media with negative electrical permittivity and magnetic permeability. Besides applications similar to those of optical metamaterials, a nanosized slab of a metamaterial for ballistic electrons, sandwiched between quantum wells of positive effective mass materials, reveals unexpected conduction properties, e.g. single or multiple room temperature negative differential conductance regions at very low voltages and with considerable peak-to-valley ratios, while the traversal time of ballistic electrons can be tuned to larger or smaller values than in the absence of the metamaterial slab. Thus, slow and fast electrons, analogous to slow and fast light, occur in metamaterials for ballistic electrons.

  8. Pulsed ion beam source

    DOE Patents [OSTI]

    Greenly, J.B.

    1997-08-12

    An improved pulsed ion beam source is disclosed having a new biasing circuit for the fast magnetic field. This circuit provides for an initial negative bias for the field created by the fast coils in the ion beam source which pre-ionize the gas in the source, ionize the gas and deliver the gas to the proper position in the accelerating gap between the anode and cathode assemblies in the ion beam source. The initial negative bias improves the interaction between the location of the nulls in the composite magnetic field in the ion beam source and the position of the gas for pre-ionization and ionization into the plasma as well as final positioning of the plasma in the accelerating gap. Improvements to the construction of the flux excluders in the anode assembly are also accomplished by fabricating them as layered structures with a high melting point, low conductivity material on the outsides with a high conductivity material in the center. 12 figs.

  9. Acceleration of electrons using an inverse free electron laser auto- accelerator

    SciTech Connect (OSTI)

    Wernick, I.K.; Marshall, T.C.

    1992-07-01

    We present data from our study of a device known as the inverse free electron laser. First, numerical simulations were performed to optimize the design parameters for an experiment that accelerates electrons in the presence of an undulator by stimulated absorption of radiation. The Columbia free electron laser (FEL) was configured as an auto-accelerator (IFELA) system; high power (MW's) FEL radiation at {approximately}1.65 mm is developed along the first section of an undulator inside a quasi-optical resonator. The electron beam then traverses a second section of undulator where a fraction of the electrons is accelerated by stimulated absorption of the 1.65 mm wavelength power developed in the first undulator section. The second undulator section has very low gain and does not generate power on its own. We have found that as much as 60% of the power generated in the first section can be absorbed in the second section, providing that the initial electron energy is chosen correctly with respect to the parameters chosen for the first and second undulators. An electron momentum spectrometer is used to monitor the distribution of electron energies as the electrons exit the IFELA. We have found; using our experimental parameters, that roughly 10% of the electrons are accelerated to energies as high as 1100 keV, in accordance with predictions from the numerical model. The appearance of high energy electrons is correlated with the abrupt absorption of millimeter power. The autoaccelerator configuration is used because there is no intense source of coherent power at the 1.65 mm design wavelength other than the FEL.

  10. Acceleration of electrons using an inverse free electron laser auto- accelerator

    SciTech Connect (OSTI)

    Wernick, I.K.; Marshall, T.C.

    1992-07-01

    We present data from our study of a device known as the inverse free electron laser. First, numerical simulations were performed to optimize the design parameters for an experiment that accelerates electrons in the presence of an undulator by stimulated absorption of radiation. The Columbia free electron laser (FEL) was configured as an auto-accelerator (IFELA) system; high power (MW`s) FEL radiation at {approximately}1.65 mm is developed along the first section of an undulator inside a quasi-optical resonator. The electron beam then traverses a second section of undulator where a fraction of the electrons is accelerated by stimulated absorption of the 1.65 mm wavelength power developed in the first undulator section. The second undulator section has very low gain and does not generate power on its own. We have found that as much as 60% of the power generated in the first section can be absorbed in the second section, providing that the initial electron energy is chosen correctly with respect to the parameters chosen for the first and second undulators. An electron momentum spectrometer is used to monitor the distribution of electron energies as the electrons exit the IFELA. We have found; using our experimental parameters, that roughly 10% of the electrons are accelerated to energies as high as 1100 keV, in accordance with predictions from the numerical model. The appearance of high energy electrons is correlated with the abrupt absorption of millimeter power. The autoaccelerator configuration is used because there is no intense source of coherent power at the 1.65 mm design wavelength other than the FEL.

  11. Generation of Femtosecond Electron and Photon Pulses

    E-Print Network [OSTI]

    Thongbai, Chitrlada; Kangrang, Nopadol; Kusoljariyakul, Keerati; Rhodes, Michael W; Rimjaem, Sakhorn; Saisut, Jatuporn; Vilaithong, Thiraphat; Wichaisirimongkol, Pathom; Wiedemann, Helmut

    2005-01-01

    Femtosecond electron and photon pulses become a tool of interesting important to study dynamics at molecular or atomic levels. Such short pulses can be generated from a system consisting of an RF-gun with a thermionic cathode, an alpha magnet as a magnetic bunch compressor, and a linear accelerator. The femtosecond electron pulses can be used directly or used as sources to produce electromagnetic radiation of equally short pulses by choosing certain kind of radiation pruduction processes. At the Fast Neutron Research Facility (Thailand), we are especially interested in production of radiation in Far-infrared and X-ray regime. In the far-infrared wavelengths which are longer than the femtosecond pulse length, the radiation is emitted coherently producing intense radiation. In the X-ray regime, development of femtosecond X-ray source is crucial for application in ultrafast science.

  12. Ion source with improved primary arc collimation

    DOE Patents [OSTI]

    Dagenhart, W.K.

    1983-12-16

    An improved negative ion source is provided in which a self-biasing, molybdenum collimator is used to define the primary electron stream arc discharge from a filament operated at a negative potential. The collimator is located between the anode and the filament. It is electrically connected to the anode by means of an appropriate size resistor such that the collimator is biased at essentially the filament voltage during operation. Initially, the full arc voltage appears across the filament to collimator until the arc discharge strikes. Then the collimator biases itself to essentially filament potential due to current flow through the resistor thus defining the primary electron stream without intercepting any appreciable arc power. The collimator aperture is slightly smaller than the anode aperture to shield the anode from the arc power which, in the past, has caused overheating and erosion of the anode collimator during extended time pulsed-beam operation of the source. With the self-biasing collimator of this invention, the ion source may be operated from short pulse periods to steady-state without destroying the anode.

  13. Ion source with improved primary arc collimation

    DOE Patents [OSTI]

    Dagenhart, William K. (Oak Ridge, TN)

    1985-01-01

    An improved negative ion source is provided in which a self-biasing, molybdenum collimator is used to define the primary electron stream arc discharge from a filament operated at a negative potential. The collimator is located between the anode and the filament. It is electrically connected to the anode by means of an appropriate size resistor such that the collimator is biased at essentially the filament voltage during operation. Initially, the full arc voltage appears across the filament to collimator until the arc discharge strikes. Then the collimator biases itself to essentially filament potential due to current flow through the resistor thus defining the primary electron stream without intercepting any appreciable arc power. The collimator aperture is slightly smaller than the anode aperture to shield the anode from the arc power, thereby preventing the exposure of the anode to the full arc power which, in the past, has caused overheating and erosion of the anode collimator during extended time pulsed-beam operation of the source. With the self-biasing collimator of this invention, the ion source may be operated from short pulse periods to steady-state without destroying the anode.

  14. Advanced Light Source QUICK FACTS

    E-Print Network [OSTI]

    : Electrons with a nominal energy of 1.9 GeV ~0.20 mm × 0.02 mm (about the width of a human hair) Electrons and x-ray light that is directed down beamlines to experiment endstations. Size of Electron Beam: 35 around the storage ring, the electrons emit synchrotron radiation--energy in the form of photons

  15. Ceramic Electron Multiplier

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Comby, G.

    1996-10-01

    The Ceramic Electron Multipliers (CEM) is a compact, robust, linear and fast multi-channel electron multiplier. The Multi Layer Ceramic Technique (MLCT) allows to build metallic dynodes inside a compact ceramic block. The activation of the metallic dynodes enhances their secondary electron emission (SEE). The CEM can be used in multi-channel photomultipliers, multi-channel light intensifiers, ion detection, spectroscopy, analysis of time of flight events, particle detection or Cherenkov imaging detectors. (auth)

  16. Controlling Graphene's Electronic Structure

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    semiconductor devices at low temperatures and high magnetic fields). Among its novel properties, graphene's electrical charge carriers (electrons and holes) move through a solid...

  17. Controlling Graphene's Electronic Structure

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    was reopened by the excess of electron charge-carriers on the graphene's surface layer. Progressive potassium deposition further enhanced the n-type doping. These results...

  18. Dual source heat pump

    DOE Patents [OSTI]

    Ecker, Amir L. (Dallas, TX); Pietsch, Joseph A. (Dallas, TX)

    1982-01-01

    What is disclosed is a heat pump apparatus for conditioning a fluid characterized by a fluid handler and path for circulating the fluid in heat exchange relationship with a refrigerant fluid; at least two refrigerant heat exchangers, one for effecting heat exchange with the fluid and a second for effecting heat exchange between refrigerant and a heat exchange fluid and the ambient air; a compressor for efficiently compressing the refrigerant; at least one throttling valve for throttling liquid refrigerant; a refrigerant circuit; refrigerant; a source of heat exchange fluid; heat exchange fluid circulating device and heat exchange fluid circuit for circulating the heat exchange fluid in heat exchange relationship with the refrigerant; and valves or switches for selecting the heat exchangers and direction of flow of the refrigerant therethrough for selecting a particular mode of operation. The heat exchange fluid provides energy for defrosting the second heat exchanger when operating in the air source mode and also provides a alternate source of heat.

  19. INSTITUTE OF PHYSICS PUBLISHING PLASMA SOURCES SCIENCE AND TECHNOLOGY Plasma Sources Sci. Technol. 10 (2001) 236249 www.iop.org/Journals/ps PII: S0963-0252(01)17082-9

    E-Print Network [OSTI]

    Chen, Francis F.

    2001-01-01

    helicon waves; the wave energy is subsequently converted to electron energy, thus raising the electronINSTITUTE OF PHYSICS PUBLISHING PLASMA SOURCES SCIENCE AND TECHNOLOGY Plasma Sources Sci. Technol-1594, USA 2 Plasma & Materials Technologies, Inc (now Trikon Technologies, Inc), 9255 Deering Avenue

  20. COMBUSTION SOURCES OF NITROGEN COMPOUNDS

    E-Print Network [OSTI]

    Brown, Nancy J.

    2011-01-01

    Rasmussen, R.A. (1976). Combustion as a source of nitrousx control for stationary combustion sources. Prog. Energy,CA, March 3-4, 1977 COMBUSTION SOURCES OF NITROGEN COMPOUNDS

  1. OLED area illumination source

    DOE Patents [OSTI]

    Foust, Donald Franklin (Scotia, NY); Duggal, Anil Raj (Niskayuna, NY); Shiang, Joseph John (Niskayuna, NY); Nealon, William Francis (Gloversville, NY); Bortscheller, Jacob Charles (Clifton Park, NY)

    2008-03-25

    The present invention relates to an area illumination light source comprising a plurality of individual OLED panels. The individual OLED panels are configured in a physically modular fashion. Each OLED panel comprising a plurality of OLED devices. Each OLED panel comprises a first electrode and a second electrode such that the power being supplied to each individual OLED panel may be varied independently. A power supply unit capable of delivering varying levels of voltage simultaneously to the first and second electrodes of each of the individual OLED panels is also provided. The area illumination light source also comprises a mount within which the OLED panels are arrayed.

  2. Electron beam coupling to a metamaterial structure

    SciTech Connect (OSTI)

    French, David M.; Shiffler, Don [Directed Energy Directorate, Air Force Research Laboratory, Albuquerque, New Mexico 87117 (United States)] [Directed Energy Directorate, Air Force Research Laboratory, Albuquerque, New Mexico 87117 (United States); Cartwright, Keith [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)] [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)

    2013-08-15

    Microwave metamaterials have shown promise in numerous applications, ranging from strip lines and antennas to metamaterial-based electron beam driven devices. In general, metamaterials allow microwave designers to obtain electromagnetic characteristics not typically available in nature. High Power Microwave (HPM) sources have in the past drawn inspiration from work done in the conventional microwave source community. In this article, the use of metamaterials in an HPM application is considered by using an effective medium model to determine the coupling of an electron beam to a metamaterial structure in a geometry similar to that of a dielectric Cerenkov maser. Use of the effective medium model allows for the analysis of a wide range of parameter space, including the “mu-negative,”“epsilon-negative,” and “double negative” regimes of the metamaterial. The physics of such a system are modeled analytically and by utilizing the particle-in-cell code ICEPIC. For this geometry and effective medium representation, optimum coupling of the electron beam to the metamaterial, and thus the optimum microwave or RF production, occurs in the epsilon negative regime of the metamaterial. Given that HPM tubes have been proposed that utilize a metamaterial, this model provides a rapid method of characterizing a source geometry that can be used to quickly understand the basic physics of such an HPM device.

  3. Simulations of Gaussian electron guns for RHIC electron lens

    SciTech Connect (OSTI)

    Pikin, A.

    2014-02-28

    Simulations of two versions of the electron gun for RHIC electron lens are presented. The electron guns have to generate an electron beam with Gaussian radial profile of the electron beam density. To achieve the Gaussian electron emission profile on the cathode we used a combination of the gun electrodes and shaping of the cathode surface. Dependence of electron gun performance parameters on the geometry of electrodes and the margins for electrodes positioning are presented.

  4. Electron uptake by iron-oxidizing phototrophic bacteria

    SciTech Connect (OSTI)

    Bose, A; Gardel, EJ; Vidoudez, C; Parra, EA; Girguis, PR

    2014-02-26

    Oxidation-reduction reactions underlie energy generation in nearly all life forms. Although most organisms use soluble oxidants and reductants, some microbes can access solid-phase materials as electron-acceptors or -donors via extracellular electron transfer. Many studies have focused on the reduction of solid-phase oxidants. Far less is known about electron uptake via microbial extracellular electron transfer, and almost nothing is known about the associated mechanisms. Here we show that the iron-oxidizing photoautotroph Rhodopseudomonas palustris TIE-1 accepts electrons from a poised electrode, with carbon dioxide as the sole carbon source/electron acceptor. Both electron uptake and ruBisCo form I expression are stimulated by light. Electron uptake also occurs in the dark, uncoupled from photosynthesis. Notably, the pioABC operon, which encodes a protein system essential for photoautotrophic growth by ferrous iron oxidation, influences electron uptake. These data reveal a previously unknown metabolic versatility of photoferrotrophs to use extracellular electron transfer for electron uptake.

  5. ELECTRONICS UPGRADE OF HIGH RESOLUTION MASS SPECTROMETERS

    SciTech Connect (OSTI)

    Mcintosh, J; Joe Cordaro, J

    2008-03-10

    High resolution mass spectrometers are specialized systems that allow researchers to determine the exact mass of samples to four significant digits by using magnetic and electronic sector mass analyzers. Many of the systems in use today at research laboratories and universities were designed and built more than two decades ago. The manufacturers of these systems have abandoned the support for some of the mass spectrometers and parts to power and control them have become scarce or obsolete. The Savannah River National Laboratory has been involved in the upgrade of the electronics and software for these legacy machines. The Electronics Upgrade of High Resolution Mass Spectrometers consists of assembling high-end commercial instrumentation from reputable manufacturers with a minimal amount of customization to replace the electronics for the older systems. By taking advantage of advances in instrumentation, precise magnet control can be achieved using high resolution current sources and continuous feedback from a high resolution hall-effect probe. The custom equipment include a precision voltage divider/summing amplifier chassis, high voltage power supply chassis and a chassis for controlling the voltage emission for the mass spectrometer source tube. The upgrade package is versatile enough to interface with valve control, vacuum and other instrumentation. Instrument communication is via a combination of Ethernet and traditional IEEE-488 GPIB protocols. The system software upgrades include precision control, feedback and spectral waveform analysis tools.

  6. Sealed Radioactive Source Accountability

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    1991-12-24

    To establish Department of Energy (DOE) interim policy and to provide guidance for sealed radioactive source accountability. The directive does not cancel any directives. Extended by DOE N 5400.10 to 12-24-93 & Extended by DOE N 5400.12 to 12-24-94.

  7. Sealed Radioactive Source Accountability

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    1994-12-22

    This Notice extends DOE N 5400.9, Sealed Radioactive Source Accountability, of 12-24-91, until 12-24-95, unless sooner superseded or rescinded. The contents of DOE N 5400.9 will be updated and incorporated in the revised DOE O 5480.11, Radiation Protection for Occupational Workers.

  8. Electron beam directed energy device and methods of using same

    DOE Patents [OSTI]

    Retsky, Michael W. (Trumbull, CT)

    2007-10-16

    A method and apparatus is disclosed for an electron beam directed energy device. The device consists of an electron gun with one or more electron beams. The device includes one or more accelerating plates with holes aligned for beam passage. The plates may be flat or preferably shaped to direct each electron beam to exit the electron gun at a predetermined orientation. In one preferred application, the device is located in outer space with individual beams that are directed to focus at a distant target to be used to impact and destroy missiles. The aimings of the separate beams are designed to overcome Coulomb repulsion. A method is also presented for directing the beams to a target considering the variable terrestrial magnetic field. In another preferred application, the electron beam is directed into the ground to produce a subsurface x-ray source to locate and/or destroy buried or otherwise hidden objects including explosive devices.

  9. Linkping University Electronic Press

    E-Print Network [OSTI]

    Zhao, Yuxiao

    Linköping University Electronic Press Strategic Plan 2009-2011 December, 2008 1 #12;1. Background As of January 1st , 2008, Linköping University Electronic Press (LiU E-Press) became a unit withinU E-Press. For these reasons, the Strategic Plan for LiU E-Press (2007- 2009) is being updated

  10. Electronic Mail Analysis Capability

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2001-01-08

    Establishes the pilot program to test the Department of Energy (DOE) Electronic Mail Analysis Capability (EMAC), which will be used to monitor and analyze outgoing and incoming electronic mail (e-mail) from the National Nuclear Security Administration (NNSA) and DOE laboratories that are engaged in nuclear weapons design or work involving special nuclear material. No cancellation.

  11. ASSISTED ELECTRONIC COMMUNICATION IN

    E-Print Network [OSTI]

    ;Department of Health Project 121-7184 Final Report 3 Executive Summary In the Assisted Electronic Project 121-7184 Final Report - 05.04.04 Kettering General NHS Hospital Trust University of Hertfordshire of Health Project 121-7184 Final Report 2 KEY to Common Abbreviations used: AEC(P) ­ Assisted Electronic

  12. Source waters Several factors influence the selection of source

    E-Print Network [OSTI]

    1 Source waters Several factors influence the selection of source waters to feed desalination plants: the location of the plant in relation to water sources available, the deliv- ery destination of the treated water, the quality of the source water, the pretreatment options available, and the ecological

  13. Magnetic-cusp, cathodic-arc source

    DOE Patents [OSTI]

    Falabella, S.

    1995-11-21

    A magnetic-cusp for a cathodic-arc source wherein the arc is confined to the desired cathode surface, provides a current path for electrons from the cathode to the anode, and utilizes electric and magnetic fields to guide ions from the cathode to a point of use, such as substrates to be coated. The magnetic-cusp insures arc stability by an easy magnetic path from anode to cathode, while the straight-through arrangement leads to high ion transmission. 3 figs.

  14. Electron: Cluster interactions

    SciTech Connect (OSTI)

    Scheidemann, A.A.; Kresin, V.V.; Knight, W.D.

    1994-02-01

    Beam depletion spectroscopy has been used to measure absolute total inelastic electron-sodium cluster collision cross sections in the energy range from E {approximately} 0.1 to E {approximately} 6 eV. The investigation focused on the closed shell clusters Na{sub 8}, Na{sub 20}, Na{sub 40}. The measured cross sections show an increase for the lowest collision energies where electron attachment is the primary scattering channel. The electron attachment cross section can be understood in terms of Langevin scattering, connecting this measurement with the polarizability of the cluster. For energies above the dissociation energy the measured electron-cluster cross section is energy independent, thus defining an electron-cluster interaction range. This interaction range increases with the cluster size.

  15. Electrons and Mirror Symmetry

    SciTech Connect (OSTI)

    Kumar, Krishna (University of Massachusetts, Amherst) [University of Massachusetts, Amherst

    2007-04-04

    The neutral weak force between an electron and a target particle, mediated by the Z boson, can be isolated by measuring the fractional change under a mirror reflection of the scattering probability of relativistic longitudinally polarized electrons off unpolarized targets. This technique yields neutral weak force measurements at a length scale of 1 femtometer, in contrast to high energy collider measurements that probe much smaller length scales. Study of the variation of the weak force over a range of length scales provides a stringent test of theory, complementing collider measurements. We describe a recent measurement of the neutral weak force between two electrons by the E158 experiment at the Stanford Linear Accelerator Center. While the weak force between an electron and positron has been extensively studied, that between two electrons had never directly been measured. We conclude by discussing prospects for even more precise measurements at future facilities.

  16. Electrons and Mirror Symmetry

    ScienceCinema (OSTI)

    Kumar, Krishna

    2009-09-01

    The neutral weak force between an electron and a target particle, mediated by the Z boson, can be isolated by measuring the fractional change under a mirror reflection of the scattering probability of relativistic longitudinally polarized electrons off unpolarized targets. This technique yields neutral weak force measurements at a length scale of 1 femtometer, in contrast to high energy collider measurements that probe much smaller length scales. Study of the variation of the weak force over a range of length scales provides a stringent test of theory, complementing collider measurements. We describe a recent measurement of the neutral weak force between two electrons by the E158 experiment at the Stanford Linear Accelerator Center. While the weak force between an electron and positron has been extensively studied, that between two electrons had never directly been measured. We conclude by discussing prospects for even more precise measurements at future facilities.

  17. Self-contained hot-hollow cathode gun source assembly

    DOE Patents [OSTI]

    Zeren, J.D.

    1984-08-01

    A self-contained hot-hollow cathode gun source assembly for use in a vacuum chamber includes a crucible block having a hot-hollow cathode gun mounted underneath and providing a hole for the magnetic deflection of the ion/electron beam into a crucible on top the block.

  18. Self-contained hot-hollow cathode gun source assembly

    DOE Patents [OSTI]

    Zeren, Joseph D. (Boulder, CO)

    1986-01-01

    A self-contained hot-hollow cathode gun source assembly for use in a vacuum chamber includes a crucible block having a hot-hollow cathode gun mounted underneath and providing a hole for the magnetic deflection of the ion/electron beam into a crucible on top the block.

  19. Theory and Design of Smith-Purcell Semiconductor Terahertz Sources 

    E-Print Network [OSTI]

    Smith, Don DeeWayne

    2013-12-06

    difficulties reaching the THz, and no THz device of any type operates on the full range at room temperature. This dissertation proposes a novel semiconductor source which utilizes the transferred-electron (Gunn) effect and the Smith-Purcell effect to operate...

  20. A high-brightness source of polarization-entangled photons

    E-Print Network [OSTI]

    Weinfurter, Harald

    A high-brightness source of polarization-entangled photons optimized for applications in free space for Quantum Computing and Department of Physics and Astronomy, University of Waterloo, Ontario N2L 3G1, Canada 3, 1090 Wien, Austria 7 Department of Electrical and Electronic Engineering, University of Bristol

  1. Science and Technology of Future Light Sources

    SciTech Connect (OSTI)

    Bergmann, Uwe; Corlett, John; Dierker, Steve; Falcone, Roger; Galayda, John; Gibson, Murray; Hastings, Jerry; Hettel, Bob; Hill, John; Hussain, Zahid; Kao, Chi-Chang; Kirz, Janos; Long, Danielle; McCurdy, Bill; Raubenheimer, Tor; Sannibale, Fernando; Seeman, John; Shen, Z. -X.; Schenoy, Gopal; Schoenlein, Bob; Shen, Qun; Stephenson, Brian; Stöhr, Joachim; Zholents, Alexander

    2009-01-28

    Many of the important challenges facing humanity, including developing alternative sources of energy and improving health, are being addressed by advances that demand the improved understanding and control of matter. While the visualization, exploration, and manipulation of macroscopic matter have long been technological goals, scientific developments in the twentieth century have focused attention on understanding matter on the atomic scale through the underlying framework of quantum mechanics. Of special interest is matter that consists of natural or artificial nanoscale building blocks defined either by atomic structural arrangements or by electron or spin formations created by collective correlation effects The essence of the challenge to the scientific community has been expressed in five grand challenges for directing matter and energy recently formulated by the Basic Energy Sciences Advisory Committee [1]. These challenges focus on increasing our understanding of, and ultimately control of, matter at the level of atoms, electrons. and spins, as illustrated in Figure 1.1, and serve the entire range of science from advanced materials to life sciences. Meeting these challenges will require new tools that extend our reach into regions of higher spatial, temporal, and energy resolution. X-rays with energies above 10 keV offer capabilities extending beyond the nanoworld shown in Figure 1.1 due to their ability to penetrate into optically opaque or thick objects. This opens the door to combining atomic level information from scattering studies with 3D information on longer length scales from real space imaging with a resolution approaching 1 nm. The investigation of multiple length scales is important in hierarchical structures, providing knowledge about function of living organisms, the atomistic origin of materials failure, the optimization of industrial synthesis, or the working of devices. Since the fundamental interaction that holds matter together is of electromagnetic origin, it is intuitively clear that electromagnetic radiation is the critical tool in the study of material properties. On the level of atoms, electrons, and spins, x-rays have proved especially valuable. Future advanced x-ray sources and instrumentation will extend the power of x-ray methods to reach greater spatial resolution, increased sensitivity, and unexplored temporal domains. The purpose of this document is threefold: (1) summarize scientific opportunities that are beyond the reach of today's x-ray sources and instrumentation; (2) summarize the requirements for advanced x-ray sources and instrumentation needed to realize these scientific opportunities, as well as potential methods of achieving them; and (3) outline the R&D required to establish the technical feasibility of these advanced x-ray sources and instrumentation.

  2. Hypernovae as possible sources of Galactic positrons

    E-Print Network [OSTI]

    Stephane Schanne; Michel Casse; Bertrand Cordier; Jacques Paul

    2004-07-15

    INTEGRAL/SPI has recently observed a strong and extended emission resulting from electron-positron annihilation located in the Galactic center region, consistent with the Galactic bulge geometry, without any counterpart at high gamma-ray energies, nor in the 1809 keV $^{26}$Al decay line. In order to explain the rate of positron injection in the Galactic bulge, estimated to more than 10$^{43}$ s$^{-1}$, the most commonly considered positron injection sources are type Ia supernovae. However, SN Ia rate estimations show that those sources fall short to explain the observed positron production rate, raising a challenging question about the nature of the Galactic positron source. In this context, a possible source of Galactic positrons could be supernova events of a new type, as the recently observed SN2003dh/GRB030329, an exploding Wolf-Rayet star (type Ic supernova) associated with a hypernova/gamma-ray burst; the question about the rate of this kind of events remains open, but could be problematically low. In this paper, we explore the possibility of positron production and escape by such an event in the framework of an asymmetric model, in which a huge amount of $^{56}$Ni is ejected in a cone with a very high velocity; the ejected material becomes quickly transparent to positrons, which spread out in the interstellar medium.

  3. Proceedings of the 10th international workshop on ECR ion sources

    SciTech Connect (OSTI)

    Meyer, F W; Kirkpatrick, M I [eds.

    1991-01-01

    This report contains papers on the following topics: Recent Developments and Future Projects on ECR Ion Sources; Operation of the New KVI ECR Ion Source at 10 GHz; Operational Experience and Status of the INS SF-ECR Ion Source; Results of the New ECR4'' 14.5 GHz ECRIS; Preliminary Performance of the AECR; Experimental Study of the Parallel and Perpendicular Particle Losses from an ECRIS Plasma; Plasma Instability in Electron Cyclotron Resonance Heated Ion Sources; The Hyperbolic Energy Analyzer; Status of ECR Source Development; The New 10 GHz CAPRICE Source; First Operation of the Texas A M ECR Ion Source; Recent Developments of the RIKEN ECR Ion Sources; The 14 GHz CAPRICE Source; Characteristics and Potential Applications of an ORNL Microwave ECR Multicusp Plasma Ion Source; ECRIPAC: The Production and Acceleration of Multiply Charged Ions Using an ECR Plasma; ECR Source for the HHIRF Tandem Accelerator; Feasibility Studies for an ECR-Generated Plasma Stripper; Production of Ion Beams by using the ECR Plasmas Cathode; A Single Stage ECR Source for Efficient Production of Radioactive Ion Beams; The Single Staged ECR Source at the TRIUMF Isotope Separator TISOL; The Continuous Wave, Optically Pumped H{sup {minus}} Source; The H{sup +} ECR Source for the LAMPF Optically Pumped Polarized Ion Source; Present Status of the Warsaw CUSP ECR Ion Source; An ECR Source for Negative Ion Production; GYRAC-D: A Device for a 200 keV ECR Plasma Production and Accumulation; Status Report of the 14.4 GHZ ECR in Legnaro; Status of JYFL-ECRIS; Report on the Uppsala ECRIS Facility and Its Planned Use for Atomic Physics; A 10 GHz ECR Ion Source for Ion-Electron and Ion-Atom Collision Studies; and Status of the ORNL ECR Source Facility for Multicharged Ion Collision Research.

  4. Compact Gamma-ray Source Technology Development Study

    SciTech Connect (OSTI)

    Anderson, S G; Gibson, D J; Rusnak, B

    2009-09-25

    This study focuses on the applicability of current accelerator and laser technologies to the construction of compact, narrow bandwidth, gamma-ray sources for DHS missions in illicit materials detection. It also identifies research and development areas in which advancement will directly benefit these light sources. In particular, we review the physics of Compton scattering based light sources and emphasize the source properties most important to Nuclear Resonance Fluorescence (NRF) applications of interest. The influences of laser and electron beam properties on the light source are examined in order to evaluate the utility of different technologies for this application. Applicable bulk and fiber-based laser systems and laser recirculation technologies are discussed and Radio Frequency (RF) Linear Accelerator (linac) technologies are examined to determine the optimal frequency and pulse formats achievable.

  5. A wide bandwidth free-electron laser with mode locking using current modulation.

    SciTech Connect (OSTI)

    Kur, E.; Dunning, D. J.; McNeil, B. W. J.; Wurtele, J.; Zholents, A. A. )

    2011-01-20

    A new scheme for mode locking a free-electron laser amplifier is proposed based on electron beam current modulation. It is found that certain properties of the original concept, based on the energy modulation of electrons, are improved including the spectral brightness of the source and the purity of the series of short pulses. Numerical comparisons are made between the new and old schemes and between a mode-locked free-electron laser and self-amplified spontaneous emission free-electron laser. Illustrative examples using a hypothetical mode-locked free-electron laser amplifier are provided. The ability to generate intense coherent radiation with a large bandwidth is demonstrated.

  6. Aerogels for electronics

    SciTech Connect (OSTI)

    Hrubesh, L.W.

    1994-10-01

    In addition to their other exceptional properties, aerogels also exhibit unusual dielectric and electronic properties due to their nano-sized structures and high porosities. For example, aerogels have the lowest dielectric constants measured for a solid material (having values approaching 1.0); they have exceptionally high dielectric resistivities and strengths (i.e., ability to insulate very high voltages); they exhibit low dielectric loss at microwave frequencies; and some aerogels are electrically conductive and photoconductive. These properties are being exploited to provide the next generation of materials for energy storage, low power consumption, and ultra-fast electronics. We are working toward adapting these unusual materials for microelectronic applications, particularly, making thin aerogel films for dielectric substrates and for energy storage devices such as supercapacitors. Measurements are presented in this paper for the dielectric and electronic properties of aerogels, including the dielectric constant, loss factor, dielectric and electrical conductivity, volume resistivity, and dielectric strength. We also describe methods to form and characterize thin aerogel films which are being developed for numerous electronic applications. Finally, some of the electronic applications proposed for aerogels are presented. Commercialization of aerogels for electronics must await further feasibility, prototype development, and cost studies, but they are one of the key materials and are sure to have a major impact on future electronics.

  7. Calibrated vapor generator source

    DOE Patents [OSTI]

    Davies, J.P.; Larson, R.A.; Goodrich, L.D.; Hall, H.J.; Stoddard, B.D.; Davis, S.G.; Kaser, T.G.; Conrad, F.J.

    1995-09-26

    A portable vapor generator is disclosed that can provide a controlled source of chemical vapors, such as, narcotic or explosive vapors. This source can be used to test and calibrate various types of vapor detection systems by providing a known amount of vapors to the system. The vapor generator is calibrated using a reference ion mobility spectrometer. A method of providing this vapor is described, as follows: explosive or narcotic is deposited on quartz wool, placed in a chamber that can be heated or cooled (depending on the vapor pressure of the material) to control the concentration of vapors in the reservoir. A controlled flow of air is pulsed over the quartz wool releasing a preset quantity of vapors at the outlet. 10 figs.

  8. Calibrated vapor generator source

    DOE Patents [OSTI]

    Davies, John P. (Idaho Falls, ID); Larson, Ronald A. (Idaho Falls, ID); Goodrich, Lorenzo D. (Shelley, ID); Hall, Harold J. (Idaho Falls, ID); Stoddard, Billy D. (Idaho Falls, ID); Davis, Sean G. (Idaho Falls, ID); Kaser, Timothy G. (Idaho Falls, ID); Conrad, Frank J. (Albuquerque, NM)

    1995-01-01

    A portable vapor generator is disclosed that can provide a controlled source of chemical vapors, such as, narcotic or explosive vapors. This source can be used to test and calibrate various types of vapor detection systems by providing a known amount of vapors to the system. The vapor generator is calibrated using a reference ion mobility spectrometer. A method of providing this vapor is described, as follows: explosive or narcotic is deposited on quartz wool, placed in a chamber that can be heated or cooled (depending on the vapor pressure of the material) to control the concentration of vapors in the reservoir. A controlled flow of air is pulsed over the quartz wool releasing a preset quantity of vapors at the outlet.

  9. Evaluated teletherapy source library

    DOE Patents [OSTI]

    Cox, Lawrence J. (Los Alamos, NM); Schach Von Wittenau, Alexis E. (Livermore, CA)

    2000-01-01

    The Evaluated Teletherapy Source Library (ETSL) is a system of hardware and software that provides for maintenance of a library of useful phase space descriptions (PSDs) of teletherapy sources used in radiation therapy for cancer treatment. The PSDs are designed to be used by PEREGRINE, the all-particle Monte Carlo dose calculation system. ETSL also stores other relevant information such as monitor unit factors (MUFs) for use with the PSDs, results of PEREGRINE calculations using the PSDs, clinical calibration measurements, and geometry descriptions sufficient for calculational purposes. Not all of this information is directly needed by PEREGRINE. It also is capable of acting as a repository for the Monte Carlo simulation history files from which the generic PSDs are derived.

  10. High current ion source

    DOE Patents [OSTI]

    Brown, Ian G. (1088 Woodside Rd., Berkeley, CA 94708); MacGill, Robert A. (645 Kern St., Richmond, CA 94805); Galvin, James E. (2 Commodore Dr. #276, Emeryville, CA 94608)

    1990-01-01

    An ion source utilizing a cathode and anode for producing an electric arc therebetween. The arc is sufficient to vaporize a portion of the cathode to form a plasma. The plasma leaves the generation region and expands through another regon. The density profile of the plasma may be flattened using a magnetic field formed within a vacuum chamber. Ions are extracted from the plasma to produce a high current broad on beam.

  11. The European Spallation Source

    SciTech Connect (OSTI)

    Peggs, S; Eshraqi, M; Hahn, H; Jansson, A; Lindroos, M; Ponton, A; Rathsman, K; Trahern, G; Bousso, S; Calaga, R; Devanz, G; Duperrier, R D; Eguia, J; Gammino, S; Moller, S P; Oyon, C; Ruber, R.J.M.Y.

    2011-03-01

    The European Spallation Source (ESS) is a 5 MW, 2.5 GeV long pulse proton linac, to be built and commissioned in Lund, Sweden. The Accelerator Design Update (ADU) project phase is under way, to be completed at the end of 2012 by the delivery of a Technical Design Report. Improvements to the 2003 ESS design will be summarised, and the latest design activities will be presented.

  12. BERNAS ION SOURCE DISCHARGE SIMULATION

    SciTech Connect (OSTI)

    RUDSKOY,I.; KULEVOY, T.V.; PETRENKO, S.V.; KUIBEDA, R.P.; SELEZNEV, D.N.; PERSHIN, V.I.; HERSHCOVITCH, A.; JOHNSON, B.M.; GUSHENETS, V.I.; OKS, E.M.; POOLE, H.J.

    2007-08-26

    The joint research and development program is continued to develop steady-state ion source of decaborane beam for ion implantation industry. Bemas ion source is the wide used ion source for ion implantation industry. The new simulation code was developed for the Bemas ion source discharge simulation. We present first results of the simulation for several materials interested in semiconductors. As well the comparison of results obtained with experimental data obtained at the ITEP ion source test-bench is presented.

  13. electronic reprint Synchrotron

    E-Print Network [OSTI]

    Hitchcock, Adam P.

    Institute for Intelligent Systems, Stuttgart, Baden-Wu¨rttemberg 70569, Germany, and d Canadian Light Source(s) of this paper may load this reprint on their own web site or institutional repository provided that this cover as specified above is not permitted without prior permission in writing from the IUCr. For further information

  14. Source Selection Guide | Department of Energy

    Energy Savers [EERE]

    Source Selection Guide Source Selection Guide Source Selection Guide More Documents & Publications Source Selection Guide Attachment FY2011-77 OPAM Policy Flash 2011-77 Attachment...

  15. Photon Source Parameters

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformationJesseworkSURVEYI/OPerformance andAreaPhotoinduced electron transfer

  16. Photon Source Parameters

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformationJesseworkSURVEYI/OPerformance andAreaPhotoinduced electron transferPhoton

  17. Invited Article: Characterization of background sources in space-based time-of-flight mass spectrometers

    SciTech Connect (OSTI)

    Gilbert, J. A.; Gershman, D. J.; Gloeckler, G.; Lundgren, R. A.; Zurbuchen, T. H.; Orlando, T. M.; McLain, J.; Steiger, R. von

    2014-09-15

    For instruments that use time-of-flight techniques to measure space plasma, there are common sources of background signals that evidence themselves in the data. The background from these sources may increase the complexity of data analysis and reduce the signal-to-noise response of the instrument, thereby diminishing the science value or usefulness of the data. This paper reviews several sources of background commonly found in time-of-flight mass spectrometers and illustrates their effect in actual data using examples from ACE-SWICS and MESSENGER-FIPS. Sources include penetrating particles and radiation, UV photons, energy straggling and angular scattering, electron stimulated desorption of ions, ion-induced electron emission, accidental coincidence events, and noise signatures from instrument electronics. Data signatures of these sources are shown, as well as mitigation strategies and design considerations for future instruments.

  18. Self-bunching electron guns

    SciTech Connect (OSTI)

    Mako, F.M.; Len, L.K. [FM Technologies, Inc., 10529-B Braddock Road, Fairfax, Virginia 22032 (United States)

    1999-05-01

    We report on three electron gun projects that are aimed at power tube and injector applications. The purpose of the work is to develop robust electron guns which produce self-bunched, high-current-density beams. We have demonstrated, in a microwave cavity, self-bunching, cold electron emission, long life, and tolerance to contamination. The cold process is based on secondary electron emission. FMT has studied using simulation codes the resonant bunching process which gives rise to high current densities (0.01{endash}5 kA/cm{sup 2}), high charge bunches (up to 500 nC/bunch), and short pulses (1{endash}100 ps) for frequencies from 1 to 12 GHz. The beam pulse width is nominally {approximately}5{percent} of the {ital rf} period. The first project is the L-Band Micro-Pulse Gun (MPG). Measurements show {approximately}40 ps long micro-bunches at {approximately}20 A/cm{sup 2} without contamination due to air exposure. Lifetime testing has been carried out for about 18 months operating at 1.25 GHz for almost 24 hours per day at a repetition rate of 300 Hz and 5 {mu}s-long macro-pulses. Approximately 5.8{times}10{sup 13} micro-bunches or 62,000 coulombs have passed through this gun and it is still working fine. The second project, the S-Band MPG, is now operational. It is functioning at a frequency of 2.85 GHz, a repetition rate of 30 Hz, with a 2 {mu}s-long macro-pulse. It produces about 45 A in the macro-pulse. The third project is a 34.2 GHz frequency-multiplied source driven by an X-Band MPG. A point design was performed at an {ital rf} output power of 150 MW at 34.2 GHz. The resulting system efficiency is 53{percent} and the gain is 60 dB. The system efficiency includes the input cavity efficiency, input driver efficiency (a 50 MW klystron at 11.4 GHz), output cavity efficiency, and the post-acceleration efficiency. {copyright} {ital 1999 American Institute of Physics.}

  19. Electron Microscope Facility

    ScienceCinema (OSTI)

    None

    2010-01-08

    Brookhaven Lab is home to one of only a few Scanning Transmision Electron Microscope (STEM) machines in the world and one of the few that can image single heavy atoms.

  20. Matter & Energy Electronics

    E-Print Network [OSTI]

    Suslick, Kenneth S.

    See also: Matter & Energy Detectors· Electronics· Technology· Medical Technology· Weapons Technology · Organic Chemistry· Reference Hydrogen chloride· Photography· Catalytic converter· Nanomedicine a series of tiny colored dots ­ each a different pigment ­ on an inert backing such as paper, plastic

  1. Toward pure electronic spectroscopy

    E-Print Network [OSTI]

    Petrovi?, Vladimir, 1978-

    2009-01-01

    In this thesis is summarized the progress toward completing our understanding of the Rydberg system of CaF and developing Pure Electronic Spectroscopy. The Rydberg system of CaF possesses a paradigmatic character due to ...

  2. VIA ELECTRONIC SUBMISSION

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    39 MacDougal Street, Third Floor * New York, New York 10012 * (212) 992-8932 * www.policyintegrity.org March 21, 2011 VIA ELECTRONIC SUBMISSION Office of the General Counsel US...

  3. Helicon wave excitation to produce energetic electrons for manufacturing semiconductors

    DOE Patents [OSTI]

    Molvik, A.W.; Ellingboe, A.R.

    1998-10-20

    A helicon plasma source is controlled by varying the axial magnetic field or rf power controlling the formation of the helicon wave. An energetic electron current is carried on the wave when the magnetic field is 90 G; but there is minimal energetic electron current when the magnetic field is 100 G in one particular plasma source. Similar performance can be expected from other helicon sources by properly adjusting the magnetic field and power to the particular geometry. This control for adjusting the production of energetic electrons can be used in the semiconductor and thin-film manufacture process. By applying energetic electrons to the insulator layer, such as silicon oxide, etching ions are attracted to the insulator layer and bombard the insulator layer at higher energy than areas that have not accumulated the energetic electrons. Thus, silicon and metal layers, which can neutralize the energetic electron currents will etch at a slower or non-existent rate. This procedure is especially advantageous in the multilayer semiconductor manufacturing because trenches can be formed that are in the range of 0.18--0.35 mm or less. 16 figs.

  4. Method for generating a plasma wave to accelerate electrons

    DOE Patents [OSTI]

    Umstadter, D.; Esarey, E.; Kim, J.K.

    1997-06-10

    The invention provides a method and apparatus for generating large amplitude nonlinear plasma waves, driven by an optimized train of independently adjustable, intense laser pulses. In the method, optimal pulse widths, interpulse spacing, and intensity profiles of each pulse are determined for each pulse in a series of pulses. A resonant region of the plasma wave phase space is found where the plasma wave is driven most efficiently by the laser pulses. The accelerator system of the invention comprises several parts: the laser system, with its pulse-shaping subsystem; the electron gun system, also called beam source, which preferably comprises photo cathode electron source and RF-LINAC accelerator; electron photo-cathode triggering system; the electron diagnostics; and the feedback system between the electron diagnostics and the laser system. The system also includes plasma source including vacuum chamber, magnetic lens, and magnetic field means. The laser system produces a train of pulses that has been optimized to maximize the axial electric field amplitude of the plasma wave, and thus the electron acceleration, using the method of the invention. 21 figs.

  5. Method for generating a plasma wave to accelerate electrons

    DOE Patents [OSTI]

    Umstadter, Donald (Ann Arbor, MI); Esarey, Eric (Chevy Chase, MD); Kim, Joon K. (Ann Arbor, MI)

    1997-01-01

    The invention provides a method and apparatus for generating large amplitude nonlinear plasma waves, driven by an optimized train of independently adjustable, intense laser pulses. In the method, optimal pulse widths, interpulse spacing, and intensity profiles of each pulse are determined for each pulse in a series of pulses. A resonant region of the plasma wave phase space is found where the plasma wave is driven most efficiently by the laser pulses. The accelerator system of the invention comprises several parts: the laser system, with its pulse-shaping subsystem; the electron gun system, also called beam source, which preferably comprises photo cathode electron source and RF-LINAC accelerator; electron photo-cathode triggering system; the electron diagnostics; and the feedback system between the electron diagnostics and the laser system. The system also includes plasma source including vacuum chamber, magnetic lens, and magnetic field means. The laser system produces a train of pulses that has been optimized to maximize the axial electric field amplitude of the plasma wave, and thus the electron acceleration, using the method of the invention.

  6. Helicon wave excitation to produce energetic electrons for manufacturing semiconductors

    DOE Patents [OSTI]

    Molvik, Arthur W. (Livermore, CA); Ellingboe, Albert R. (Fremont, CA)

    1998-01-01

    A helicon plasma source is controlled by varying the axial magnetic field or rf power controlling the formation of the helicon wave. An energetic electron current is carried on the wave when the magnetic field is 90 G; but there is minimal energetic electron current when the magnetic field is 100 G in one particular plasma source. Similar performance can be expected from other helicon sources by properly adjusting the magnetic field and power to the particular geometry. This control for adjusting the production of energetic electrons can be used in the semiconductor and thin-film manufacture process. By applying energetic electrons to the insulator layer, such as silicon oxide, etching ions are attracted to the insulator layer and bombard the insulator layer at higher energy than areas that have not accumulated the energetic electrons. Thus, silicon and metal layers, which can neutralize the energetic electron currents will etch at a slower or non-existent rate. This procedure is especially advantageous in the multilayer semiconductor manufacturing because trenches can be formed that are in the range of 0.18-0.35 mm or less.

  7. STATUS REPORT ON THE "MERGING" OF THE ELECTRON-CLOUD CODE POSINST WITH THE 3-D ACCELERATOR PIC CODE WARP*

    E-Print Network [OSTI]

    Furman, Miguel

    primary and secondary sources of electrons, beam bunch kicks, a particle mover, and diagnostics. WARP of accelerator beam lines, parallelism, advanced diagnostics and interactivity through the Python interpreter and velocities). Currently, POSINST provides initial and secondary sources of electrons, beam bunch kicks

  8. 1018 JOURNAL OF MICROELECTROMECHANICAL SYSTEMS, VOL. 13, NO. 6, DECEMBER 2004 Limit Cycle Oscillations in CW Laser-Driven NEMS

    E-Print Network [OSTI]

    Rand, Richard H.

    method (FEM), laser drive, limit cycle oscillation, self-oscillation, thermal stress. I. INTRODUCTION1018 JOURNAL OF MICROELECTROMECHANICAL SYSTEMS, VOL. 13, NO. 6, DECEMBER 2004 Limit Cycle, Richard Rand, Alan Zehnder, Jeevak Parpia, and Harold Craighead, Member, IEEE Abstract--Limit cycle

  9. Laser-Driven Magnetic-Flux Compression in High-Energy-Density Plasmas O. V. Gotchev,1,2,3

    E-Print Network [OSTI]

    of magnetic field compression to many tens of megagauss in cylindrical implosions of inertial confinement.57.Àz, 52.25.Xz, 52.55.Lf In the magnetic fusion energy (MFE) concept, a strong magnetic field confines with a strong external field (>50 kG) from a specially developed magnetic pulse generator. This seed field

  10. Cooling system for electronic components

    DOE Patents [OSTI]

    Anderl, William James; Colgan, Evan George; Gerken, James Dorance; Marroquin, Christopher Michael; Tian, Shurong

    2015-12-15

    Embodiments of the present invention provide for non interruptive fluid cooling of an electronic enclosure. One or more electronic component packages may be removable from a circuit card having a fluid flow system. When installed, the electronic component packages are coincident to and in a thermal relationship with the fluid flow system. If a particular electronic component package becomes non-functional, it may be removed from the electronic enclosure without affecting either the fluid flow system or other neighboring electronic component packages.

  11. Final Technical Report- Back-gate Field Emission-based Cathode RF Electron Gun

    SciTech Connect (OSTI)

    McGuire, Gary; Martin, Allen; Noonan, John

    2010-10-30

    The objective was to complete the design of an electron gun which utilizes a radio frequency (RF) power source to apply a voltage to a field emission (FE) cathode, a so called cold cathode, in order to produce an electron beam. The concept of the RF electron gun was originally conceived at Argonne National Laboratory but never reduced to practice. The research allowed the completion of the design based upon the integration of the FE electron source. Compared to other electron guns, the RF gun is very compact, less than one third the size of other comparable guns, and produces a high energy (to several MeV), high quality, high power electron beam with a long focal length with high repetition rates. The resultant electron gun may be used in welding, materials processing, analytical equipment and waste treatment.

  12. Pseudopotential for the electron-electron interaction

    E-Print Network [OSTI]

    Lloyd-Williams, J. H.; Needs, R. J.; Conduit, G. J.

    2015-08-05

    -of-mass frame with wave vector k ? 0 and angular momentum quantum number `. The Hamiltonian in atomic units is ? 1r2 ddr (r2 d? dr ) + `(`+1) r2 ?+ V (r)? = k2?, and the repulsive Coulomb potential is V (r) = 1/r. The proposed pseudopotential is identical... to fermion anti- symmetry. We solve for the energy of two interacting electrons in the parabolic trap within the center-of-mass frame in which the interacting Hamiltonian for relative mo- tion is Hˆ = ? 1r2 ddr (r2 ddr ) + ?2r2/4 + `(`+ 1)/r2 + V (r), where V...

  13. Sources of tritium

    SciTech Connect (OSTI)

    Phillips, J.E.; Easterly, C.E.

    1980-12-01

    A review of tritium sources is presented. The tritium production and release rates are discussed for light water reactors (LWRs), heavy water reactors (HWRs), high temperature gas cooled reactors (HTGRs), liquid metal fast breeder reactors (LMFBRs), and molten salt breeder reactors (MSBRs). In addition, release rates are discussed for tritium production facilities, fuel reprocessing plants, weapons detonations, and fusion reactors. A discussion of the chemical form of the release is included. The energy producing facilities are ranked in order of increasing tritium production and release. The ranking is: HTGRs, LWRs, LMFBRs, MSBRs, and HWRs. The majority of tritium has been released in the form of tritiated water.

  14. Compact ion accelerator source

    DOE Patents [OSTI]

    Schenkel, Thomas; Persaud, Arun; Kapadia, Rehan; Javey, Ali

    2014-04-29

    An ion source includes a conductive substrate, the substrate including a plurality of conductive nanostructures with free-standing tips formed on the substrate. A conductive catalytic coating is formed on the nanostructures and substrate for dissociation of a molecular species into an atomic species, the molecular species being brought in contact with the catalytic coating. A target electrode placed apart from the substrate, the target electrode being biased relative to the substrate with a first bias voltage to ionize the atomic species in proximity to the free-standing tips and attract the ionized atomic species from the substrate in the direction of the target electrode.

  15. Photon Source Parameters

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass mapSpeeding access| DepartmentPeerFederal FleetUp in thePhoton Source Parameters Print

  16. Photon Source Parameters

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass mapSpeeding access| DepartmentPeerFederal FleetUp in thePhoton Source Parameters

  17. Heat Source Lire,

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverse (Journalvivo Low-DoseOptions for AccidentalHealth, Safety,FOIAHeatSource

  18. Sifting Through a Trillion Electrons

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Sifting Through a Trillion Electrons Sifting Through a Trillion Electrons Berkeley researchers design strategies for extracting interesting data from massive scientific datasets...

  19. Measuring Speedy Electrons in Silicon

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Laser, Supercomputer Measure Speedy Electrons in Silicon Laser, Supercomputer Measure Speedy Electrons in Silicon Simulations at NERSC Help Illuminate Attosecond Laser Experiment...

  20. Electron Trapping by Molecular Vibration

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Electron Trapping by Molecular Vibration Print In photoelectron spectroscopy experiments performed at the ALS, a group of researchers has found that electronic transitions normally...

  1. Electron Trapping by Molecular Vibration

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Electron Trapping by Molecular Vibration Electron Trapping by Molecular Vibration Print Wednesday, 27 April 2005 00:00 In photoelectron spectroscopy experiments performed at the...

  2. Reversible Electron Beam Heating for Suppression of Microbunching Instabilities at Free-Electron Lasers

    SciTech Connect (OSTI)

    Behrens, Christopher; /DESY; Huang, Zhirong; Xiang, Dao; /SLAC

    2012-05-30

    The presence of microbunching instabilities due to the compression of high-brightness electron beams at existing and future x-ray free-electron lasers (FELs) results in restrictions on the attainable lasing performance and renders beam imaging with optical transition radiation impossible. The instability can be suppressed by introducing additional energy spread, i.e., heating the electron beam, as demonstrated by the successful operation of the laser heater system at the Linac Coherent Light Source. The increased energy spread is typically tolerable for self-amplified spontaneous emission FELs but limits the effectiveness of advanced FEL schemes such as seeding. In this paper, we present a reversible electron beam heating system based on two transverse deflecting radio-frequency structures (TDSs) upstream and downstream of a magnetic bunch compressor chicane. The additional energy spread is introduced in the first TDS, which suppresses the microbunching instability, and then is eliminated in the second TDS. We show the feasibility of the microbunching gain suppression based on calculations and simulations including the effects of coherent synchrotron radiation. Acceptable electron beam and radio-frequency jitter are identified, and inherent options for diagnostics and on-line monitoring of the electron beam's longitudinal phase space are discussed.

  3. Heating and Acceleration of Intracluster Medium Electrons by Turbulence

    E-Print Network [OSTI]

    Vahé Petrosian; William E. East

    2008-02-06

    In this paper we investigate the feasibility of bremsstrahlung radiation from `nonthermal' electrons as a source of hard X-rays from the intracluster medium of clusters of galaxies. With an exact treatment of the Coulomb collisions in a Fokker-Planck analysis of the electron distribution we find that the severe difficulties with lifetimes of `nonthermal' particles found earlier by Petrosian (2001) using a cold target model remain problematic. We then address possible acceleration of background electrons into a nonthermal tail. We assume a simplified but generic acceleration rate and determine the expected evolution of an initially Maxwellian distribution of electrons. We find that strong nonthermal components arise only for rapid rate of acceleration which also heats up the entire plasma. These results confirm the conclusion that if the observed `nonthermal' excesses are due to some process accelerating the background thermal electrons this process must be short lived.

  4. Femtosecond Electron and Photon Pulses Facility in Thailand

    SciTech Connect (OSTI)

    Rimjaem, S.; Thongbai, C.; Jinamoon, V.; Kangrang, N.; Kusoljariyakul, K.; Saisut, J.; Vilaithong, T.; Rhodes, M. W.; Wichaisirimongkol, P.

    2007-01-19

    Femtosecond electron and photon pulses facility has been established as SURIYA project at the Fast Neutron Research Facility (FNRF). Femtosecond electron bunches can be generated from a system consisting of an RF gun with a thermionic cathode, an alpha magnet as an magnetic bunch compressor, and a linear accelerator as a post acceleration section. Femtosecond electron pulses can be used directly or used as a source to produce equally short electromagnetic (EM) radiation pulses via certain kind of radiation production processes. At SURIYA project, we are interested especially in production of radiation in Far-infrared (FIR) regime. At these wavelengths, the radiation from femtosecond electron pulses is emitted coherently resulting in high intensity radiation. Overview of the facility, the generation of femtosecond electron bunches, the theoretical background of coherent transition radiation and the recent experimental results will be presented and discussed in this paper.

  5. Electron Heating in a Relativistic, Weibel-Unstable Plasma

    E-Print Network [OSTI]

    Kumar, Rahul; Gedalin, Michael

    2015-01-01

    The dynamics of two initially unmagnetized relativistic counter-streaming homogeneous ion-electron plasma beams are simulated in two dimensions using the particle-in-cell (PIC) method. It is shown that current filaments, which form due to the Weibel instability, develop a large scale longitudinal electric field in the direction opposite to the current carried by the filaments as predicted by theory. Fast moving ions in the current filaments decelerate due to this longitudinal electric field. The same longitudinal electric field, which is partially inductive and partially electrostatic, is identified as the main source of acceleration of electrons in the current filaments. The transverse electric field, though larger than the longitudinal one, is shown to play a smaller role in heating electrons, contrary to previous claims. It is found that, in 1D, the electrons become strongly magnetized and are \\textit{not} accelerated beyond their initial kinetic energy. Rather, the heating of the electrons is enhanced by ...

  6. Microscopy with slow electrons: from LEEM to XPEEM

    ScienceCinema (OSTI)

    Bauer, Ernst [Arizona State University, Phoenix, Arizona, United States

    2010-01-08

    The short penetration and escape depth of electrons with energies below 1 keV make them ideally suited for the study of surfaces and ultrathin films. The combination of the low energy electrons and the high lateral resolution of a microscope produces a powerful method for the characterization of nanostructures on bulk samples, in particular if the microscope is equipped with an imaging energy filter and connected to a synchrotron radiation source. Comprehensive characterization by imaging, diffraction, and spectroscope of the structural, chemical, and magnetic properties is then possible. The Talk will describe the various imaging techniques in using reflected and emitted electrons in low-energy electron microscopy (LEEM) and x-ray photoemission electron microscopy (XPEEM), with an emphasis on magnetic materials with spin-polarized LEEM and x-ray magnetic circular dichroism PEEM. The talk with end with an outlook on future possibilities.

  7. Experimental Investigation of Electron-Acoustic Waves in Electron Plasmas

    E-Print Network [OSTI]

    California at San Diego, University of

    Experimental Investigation of Electron-Acoustic Waves in Electron Plasmas Andrey A. Kabantsev , F Electron-acoustic wave (EAW) solutions of the linearized electrostatic Vlasov equations have usually been USA 92093-0319 Dipt. di Fisica and INFM, Univ. della Calabria, 87036 Rende, Italy Abstract. Electron-acoustic

  8. Roadmap: Electronic Media Electronic Media Sports Production Bachelor of Science

    E-Print Network [OSTI]

    Sheridan, Scott

    Roadmap: Electronic Media ­ Electronic Media Sports Production ­ Bachelor of Science [CI­2013 Page 1 of 4 | Last Updated: 23-May-12/LNHD This roadmap is a recommended semester-by-semester plan requirement #12;Roadmap: Electronic Media ­ Electronic Media Sports Production ­ Bachelor of Science [CI

  9. An electronic radiation of blackbody: Cosmic electron background

    E-Print Network [OSTI]

    Jian-Miin Liu

    2008-02-23

    The Universe owns the electronic radiation of blackbody at temperature 2.725 K, which we call the cosmic electron background. We calculate its radiation spectrum. The energy distribution of number density of electrons in the cosmic electron background becomes zero as energy goes to both zero and infinity. It has one maximum peak near the energy level of 10**(-23) J.

  10. Electronic Survey Methodology Page 1 Electronic Survey Methodology

    E-Print Network [OSTI]

    Nonnecke, Blair

    Electronic Survey Methodology Page 1 Electronic Survey Methodology: A Case Study in Reaching Hard, Maryland preece@umbc.edu 2002 © Andrews, Nonnecke and Preece #12;Electronic Survey Methodology Page 2 Conducting Research on the Internet: Electronic survey Design, Development and Implementation Guidelines

  11. Unified single-photon and single-electron counting statistics: From cavity QED to electron transport

    SciTech Connect (OSTI)

    Lambert, Neill [Advanced Science Institute, RIKEN, Saitama 351-0198 (Japan); Chen, Yueh-Nan [Department of Physics and National Center for Theoretical Sciences, National Cheng-Kung University, Tainan 701, Taiwan (China); Nori, Franco [Advanced Science Institute, RIKEN, Saitama 351-0198 (Japan); Physics Department, University of Michigan, Ann Arbor, MI 48109-1040 (United States)

    2010-12-15

    A key ingredient of cavity QED is the coupling between the discrete energy levels of an atom and photons in a single-mode cavity. The addition of periodic ultrashort laser pulses allows one to use such a system as a source of single photons--a vital ingredient in quantum information and optical computing schemes. Here we analyze and time-adjust the photon-counting statistics of such a single-photon source and show that the photon statistics can be described by a simple transport-like nonequilibrium model. We then show that there is a one-to-one correspondence of this model to that of nonequilibrium transport of electrons through a double quantum dot nanostructure, unifying the fields of photon-counting statistics and electron-transport statistics. This correspondence empowers us to adapt several tools previously used for detecting quantum behavior in electron-transport systems (e.g., super-Poissonian shot noise and an extension of the Leggett-Garg inequality) to single-photon-source experiments.

  12. Electron microscope phase enhancement

    DOE Patents [OSTI]

    Jin, Jian; Glaeser, Robert M.

    2010-06-15

    A microfabricated electron phase shift element is used for modifying the phase characteristics of an electron beam passing though its center aperture, while not affecting the more divergent portion of an incident beam to selectively provide a ninety-degree phase shift to the unscattered beam in the back focal plan of the objective lens, in order to realize Zernike-type, in-focus phase contrast in an electron microscope. One application of the element is to increase the contrast of an electron microscope for viewing weakly scattering samples while in focus. Typical weakly scattering samples include biological samples such as macromolecules, or perhaps cells. Preliminary experimental images demonstrate that these devices do apply a ninety degree phase shift as expected. Electrostatic calculations have been used to determine that fringing fields in the region of the scattered electron beams will cause a negligible phase shift as long as the ratio of electrode length to the transverse feature-size aperture is about 5:1. Calculations are underway to determine the feasibility of aspect smaller aspect ratios of about 3:1 and about 2:1.

  13. Negative differential resistance due to single-electron switching C. P. Heij, D. C. Dixon, P. Hadley,a)

    E-Print Network [OSTI]

    American Institute of Physics. S0003-6951 99 00607-5 Single-electron tunneling devices offer a means to ma--have been extensively discussed in literature regarding resonant tunnel diodes.2 Single- electron NDR has, merely traps charge entering from the source, and so acts as an ``electron box.'' 5 The two islands

  14. Gas phase electronic spectra of the linear carbon chains HC2n1H ,,n36,9...

    E-Print Network [OSTI]

    Maier, John Paul

    Gas phase electronic spectra of the linear carbon chains HC2n¿1H ,,nÄ3­6,9... H. Ding, T. W resonant two-color two-photon ionization technique coupled to a supersonic plasma source. The electronic using DFT, MP2, and state-averaged CASSCF theories. The three lowest dipole allowed electronic

  15. IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 20, NO. 6, NOVEMBER 2005 1499 Custom Spectral Shaping for EMI Reduction in

    E-Print Network [OSTI]

    IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 20, NO. 6, NOVEMBER 2005 1499 Custom Spectral Shaping), electronic ballast, frequency modulation (FM), resonant inverter, spread spectrum. I. INTRODUCTION HIGH-FREQUENCY (HF) ac sources are used in a va- riety of applications, including electronic ballasts where HF

  16. Empirical Determination of the Energy Loss Rate of Accelerated Electrons in a Well-Observed Solar Flare

    E-Print Network [OSTI]

    Piana, Michele

    & Michele Piana1,3 ABSTRACT We present electron images of an extended solar flare source, deduced from the impulsive phase of a solar flare typically appears in the form of accelerated electrons. In the generallyEmpirical Determination of the Energy Loss Rate of Accelerated Electrons in a Well-Observed Solar

  17. Advanced Photon Source Upgrade Project

    ScienceCinema (OSTI)

    Mitchell, John; Gibson, Murray; Young, Linda; Joachimiak, Andrzej

    2013-04-19

    Upgrade to Advanced Photon Source announced by Department Of Energy. Read more: http://go.usa.gov/ivZ

  18. Performance of an inverted ion source

    SciTech Connect (OSTI)

    Salvadori, M. C.; Teixeira, F. S.; Sgubin, L. G.; Araujo, W. W. R.; Spirin, R. E.; Oks, E. M.; Brown, I. G.

    2013-02-15

    Whereas energetic ion beams are conventionally produced by extracting ions (say, positive ions) from a plasma that is held at high (positive) potential, with ion energy determined by the potential drop through which the ions fall in the beam formation electrode system, in the device described here the plasma and its electronics are held at ground potential and the ion beam is formed and injected energetically into a space maintained at high (negative) potential. We refer to this configuration as an 'inverted ion source.' This approach allows considerable savings both technologically and economically, rendering feasible some ion beam applications, in particular small-scale ion implantation, that might otherwise not be possible for many researchers and laboratories. We have developed a device of this kind utilizing a metal vapor vacuum arc plasma source, and explored its operation and beam characteristics over a range of parameter variation. The downstream beam current has been measured as a function of extraction voltage (5-35 kV), arc current (50-230 A), metal ion species (Ti, Nb, Au), and extractor grid spacing and beamlet aperture size (3, 4, and 5 mm). The downstream ion beam current as measured by a magnetically-suppressed Faraday cup was up to as high as 600 mA, and with parametric variation quite similar to that found for the more conventional metal vapor vacuum arc ion source.

  19. X-ray source assembly having enhanced output stability, and fluid stream analysis applications thereof

    DOE Patents [OSTI]

    Radley, Ian; Bievenue, Thomas J.; Burdett Jr., John H.; Gallagher, Brian W.; Shakshober, Stuart M.; Chen, Zewu; Moore, Michael D.

    2007-04-24

    An x-ray source assembly (2700) and method of operation are provided having enhanced output stability. The assembly includes an anode (2125) having a source spot upon which electrons (2120) impinge and a control system (2715/2720) for controlling position of the anode source spot relative to an output structure. The control system can maintain the anode source spot location relative to the output structure (2710) notwithstanding a change in one or more operating conditions of the x-ray source assembly. One aspect of the disclosed invention is most amenable to the analysis of sulfur in petroleum-based fuels.

  20. X-ray source assembly having enhanced output stability, and fluid stream analysis applications thereof

    DOE Patents [OSTI]

    Radley, Ian (Glenmont, NY); Bievenue, Thomas J. (Delmar, NY); Burdett, John H. (Charlton, NY); Gallagher, Brian W. (Guilderland, NY); Shakshober, Stuart M. (Hudson, NY); Chen, Zewu (Schenectady, NY); Moore, Michael D. (Alplaus, NY)

    2008-06-08

    An x-ray source assembly and method of operation are provided having enhanced output stability. The assembly includes an anode having a source spot upon which electrons impinge and a control system for controlling position of the anode source spot relative to an output structure. The control system can maintain the anode source spot location relative to the output structure notwithstanding a change in one or more operating conditions of the x-ray source assembly. One aspect of the disclosed invention is most amenable to the analysis of sulfur in petroleum-based fuels.